diff --git a/apps/web/src/components/EditorPane.tsx b/apps/web/src/components/EditorPane.tsx
index 3093af15..d333ac26 100644
--- a/apps/web/src/components/EditorPane.tsx
+++ b/apps/web/src/components/EditorPane.tsx
@@ -95,6 +95,15 @@ const MarkdownSourceEditor = lazy(() =>
 import { sanitizeAndScopeCss } from "@/lib/css-sandbox";
 import { RevisionHistoryDialog } from "./dialogs/RevisionHistoryDialog";
 import { ExternalLinkDialog } from "./dialogs/ExternalLinkDialog";
+import { MathFormulaDialog } from "./dialogs/MathFormulaDialog";
+import { EditorBlockDragHandle } from "./editor/EditorBlockDragHandle";
+import {
+  applyMathFormula,
+  deleteMathFormula,
+  resolveMathFormulaTarget,
+  selectedTextAsLatex,
+  type MathFormulaDraft,
+} from "./editor/math-formula";
 import { memoShareQueryKey, ShareMemoDialog } from "./dialogs/ShareMemoDialog";
 import { ShareNoteImageDialog } from "./dialogs/ShareNoteImageDialog";
 import { AiAssistantDialog, type AiAssistantAnchor } from "./dialogs/AiAssistantDialog";
@@ -255,6 +264,7 @@ import {
   getNoteLinkFromEventTarget,
   getNoteLinkHintPosition,
   getResourceFilesFromDataTransfer,
+  shouldInsertDroppedResourceFiles,
   isCreatedMemoEditorFocused,
   isEditorReady,
   MemoSaveRequestError,
@@ -446,6 +456,8 @@ const RichEditorPane = ({
     showTextField: true,
     canRemove: false,
   });
+  const [mathFormulaOpen, setMathFormulaOpen] = useState(false);
+  const [mathFormulaDraft, setMathFormulaDraft] = useState<MathFormulaDraft | null>(null);
   const {
     menuTarget: resourceMenuTarget,
     dialog: resourceDialog,
@@ -575,6 +587,7 @@ const RichEditorPane = ({
     setAiInsertionTarget(null);
     closeNoteReplaceRef.current();
     setExternalLinkDialogOpen(false);
+    setMathFormulaOpen(false);
     setNoteLinkPickerOpen(false);
   }, [desktopReadingProtection]);
 
@@ -590,6 +603,12 @@ const RichEditorPane = ({
   const mobileSaveTimerRef = useRef<number | null>(null);
   const fileInputRef = useRef<HTMLInputElement | null>(null);
   const openExternalLinkDialogRef = useRef<() => void>(() => undefined);
+  const openMathFormulaRef = useRef<(kind?: "inline" | "block") => void>(() => undefined);
+  const mathClickRef = useRef<(node: { attrs: Record<string, unknown> }, pos: number, kind: "inline" | "block") => void>(() => undefined);
+  const mathematicsExtensionsRef = useRef(createEdgeEverMathematics({
+    onInlineClick: (node, pos) => mathClickRef.current(node, pos, "inline"),
+    onBlockClick: (node, pos) => mathClickRef.current(node, pos, "block"),
+  }));
   const slashCommandLabelsRef = useRef<SlashCommandLabels>({
     menu: "",
     empty: "",
@@ -612,6 +631,8 @@ const RichEditorPane = ({
       divider: "",
       fold: "",
       table: "",
+      "inline-math": "",
+      "block-math": "",
       "current-date": "",
       "current-time": "",
       "current-date-time": "",
@@ -646,6 +667,8 @@ const RichEditorPane = ({
       divider: t("editorToolbar.horizontalRule"),
       fold: t("editorToolbar.fold"),
       table: t("editorToolbar.table"),
+      "inline-math": t("editorToolbar.math"),
+      "block-math": t("editorToolbar.blockMath"),
       "current-date": t("slashMenu.items.currentDate"),
       "current-time": t("slashMenu.items.currentTime"),
       "current-date-time": t("slashMenu.items.currentDateTime"),
@@ -661,6 +684,7 @@ const RichEditorPane = ({
       openAttachmentPicker: () => fileInputRef.current?.click(),
       openExternalLinkPicker: () => openExternalLinkDialogRef.current(),
       openNoteLinkPicker: () => setNoteLinkPickerOpen(true),
+      openMathFormula: (kind) => openMathFormulaRef.current(kind),
     };
   }
   const slashCommandExtensionRef = useRef<ReturnType<typeof createSlashCommandExtension> | null>(null);
@@ -1064,8 +1088,12 @@ const RichEditorPane = ({
   const editor = useEditor({
     extensions: [
       ...createEdgeEverDocumentExtensions({
-        mathematics: createEdgeEverMathematics(),
-        starterKit: { codeBlock: false, link: false },
+        mathematics: mathematicsExtensionsRef.current,
+        starterKit: {
+          codeBlock: false,
+          link: false,
+          dropcursor: { color: "#16A06E", width: 2 },
+        },
         image: false,
         gallery: EditableImageGallery,
         pdf: PdfAttachment,
@@ -1215,15 +1243,16 @@ const RichEditorPane = ({
         insertResourceFiles(files);
         return true;
       },
-      handleDrop: (_view, event) => {
-        const files = getResourceFilesFromDataTransfer(event.dataTransfer);
-
-        if (files.length === 0) {
+      handleDrop: (view, event) => {
+        if (!shouldInsertDroppedResourceFiles({
+          dataTransfer: event.dataTransfer,
+          isInternalNodeDrag: Boolean(view.dragging),
+        })) {
           return false;
         }
 
         event.preventDefault();
-        insertResourceFiles(files);
+        insertResourceFiles(getResourceFilesFromDataTransfer(event.dataTransfer));
         return true;
       },
     },
@@ -1350,6 +1379,42 @@ const RichEditorPane = ({
 
   openExternalLinkDialogRef.current = openExternalLinkDialog;
 
+  const openMathFormula = useCallback((kind: "inline" | "block" = "inline") => {
+    if (effectiveReadOnly || !isEditorReady(editor) || useMarkdownSourceEditor || useMobilePlainTextEditor) {
+      return;
+    }
+
+    const existing = resolveMathFormulaTarget(editor);
+    if (existing) {
+      setMathFormulaDraft(existing);
+      setMathFormulaOpen(true);
+      return;
+    }
+
+    const { from, to } = editor.state.selection;
+    setMathFormulaDraft({
+      kind,
+      latex: selectedTextAsLatex(editor),
+      from,
+      to,
+    });
+    setMathFormulaOpen(true);
+  }, [editor, effectiveReadOnly, useMarkdownSourceEditor, useMobilePlainTextEditor]);
+
+  openMathFormulaRef.current = openMathFormula;
+  mathClickRef.current = (_node, pos, kind) => {
+    if (effectiveReadOnly || !isEditorReady(editor) || useMarkdownSourceEditor || useMobilePlainTextEditor) {
+      return;
+    }
+    const existing = resolveMathFormulaTarget(editor, pos);
+    setMathFormulaDraft(existing ?? {
+      kind,
+      latex: String(_node.attrs.latex ?? ""),
+      pos,
+    });
+    setMathFormulaOpen(true);
+  };
+
   const applyExternalLink = useCallback(
     ({ href, text }: { href: string; text: string }) => {
       if (effectiveReadOnly) {
@@ -3396,6 +3461,25 @@ const RichEditorPane = ({
         onApply={applyExternalLink}
         onRemove={removeExternalLink}
       />
+      <MathFormulaDialog
+        open={mathFormulaOpen}
+        draft={mathFormulaDraft}
+        onOpenChange={setMathFormulaOpen}
+        onApply={(draft) => {
+          if (!isEditorReady(editor) || effectiveReadOnly) return;
+          editor.commands.focus();
+          applyMathFormula(editor, draft);
+        }}
+        onRemove={
+          mathFormulaDraft && typeof mathFormulaDraft.pos === "number"
+            ? () => {
+              if (!isEditorReady(editor) || effectiveReadOnly) return;
+              editor.commands.focus();
+              deleteMathFormula(editor, { kind: mathFormulaDraft.kind, pos: mathFormulaDraft.pos as number });
+            }
+            : undefined
+        }
+      />
       {noteLinkPickerOpen && (
         <EditorNoteLinkPicker
           query={noteLinkQuery}
@@ -3818,6 +3902,7 @@ const RichEditorPane = ({
             onPickExternalLink={openExternalLinkDialog}
             externalLinkActive={externalLinkActive}
             onPickNoteLink={() => setNoteLinkPickerOpen(true)}
+            onPickMathFormula={() => openMathFormula()}
           />
         )}
         <EditorSaveRecoveryBanner
@@ -3983,6 +4068,7 @@ const RichEditorPane = ({
               </div>
             ) : (
               <div
+                className="relative"
                 onMouseOver={handleEditorMouseOver}
                 onMouseOut={handleEditorMouseOut}
                 onFocusCapture={handleEditorFocusCapture}
@@ -4005,6 +4091,9 @@ const RichEditorPane = ({
                     {t("aiAssistant.openForSelection")}
                   </Button>
                 </BubbleMenu>
+                {!isMobileViewport && !effectiveReadOnly && isEditorReady(editor) ? (
+                  <EditorBlockDragHandle editor={editor} />
+                ) : null}
                 <EditorContent editor={editor} />
               </div>
             )}
diff --git a/apps/web/src/components/EditorToolbar.tsx b/apps/web/src/components/EditorToolbar.tsx
index 029a8e95..7ba2d415 100644
--- a/apps/web/src/components/EditorToolbar.tsx
+++ b/apps/web/src/components/EditorToolbar.tsx
@@ -18,6 +18,7 @@ import {
   Paperclip,
   Link,
   Link2,
+  Sigma,
   ChevronDown,
   ChevronUp,
 } from "lucide-react";
@@ -155,6 +156,7 @@ export const EditorToolbar = ({
   onPickAttachment,
   onPickExternalLink,
   onPickNoteLink,
+  onPickMathFormula,
   externalLinkActive = false,
 }: {
   editor: Editor | null;
@@ -166,6 +168,7 @@ export const EditorToolbar = ({
   /** Insert or edit an external hyperlink (not a note reference). */
   onPickExternalLink?: () => void;
   onPickNoteLink?: () => void;
+  onPickMathFormula?: () => void;
   externalLinkActive?: boolean;
 }) => {
   const { t } = useTranslation();
@@ -564,6 +567,16 @@ export const EditorToolbar = ({
           >
             <ChartNoAxesCombined className="h-4 w-4" />
           </EditorToolbarButton>
+          {onPickMathFormula && (
+            <EditorToolbarButton
+              title={t("editorToolbar.math")}
+              active={isActive("inlineMath") || isActive("blockMath")}
+              disabled={disabled}
+              onClick={onPickMathFormula}
+            >
+              <Sigma className="h-4 w-4" />
+            </EditorToolbarButton>
+          )}
           <EditorToolbarButton
             title={t("editorToolbar.horizontalRule")}
             disabled={disabled}
diff --git a/apps/web/src/components/dialogs/MathFormulaDialog.tsx b/apps/web/src/components/dialogs/MathFormulaDialog.tsx
new file mode 100644
index 00000000..8e1203c0
--- /dev/null
+++ b/apps/web/src/components/dialogs/MathFormulaDialog.tsx
@@ -0,0 +1,201 @@
+import { useEffect, useId, useMemo, useRef, useState } from "react";
+import { useTranslation } from "react-i18next";
+import katex from "katex";
+import { Sigma } from "lucide-react";
+import { Button } from "@/components/ui/button";
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle,
+} from "@/components/ui/dialog";
+import type { MathFormulaDraft, MathFormulaKind } from "@/components/editor/math-formula";
+
+const renderPreviewHtml = (latex: string, kind: MathFormulaKind) => {
+  const trimmed = latex.trim();
+  if (!trimmed) return "";
+  try {
+    return katex.renderToString(trimmed, {
+      displayMode: kind === "block",
+      throwOnError: false,
+      strict: "warn",
+      trust: false,
+    });
+  } catch {
+    return "";
+  }
+};
+
+export const MathFormulaDialog = ({
+  open,
+  draft,
+  onOpenChange,
+  onApply,
+  onRemove,
+}: {
+  open: boolean;
+  draft: MathFormulaDraft | null;
+  onOpenChange: (open: boolean) => void;
+  onApply: (draft: MathFormulaDraft) => void;
+  onRemove?: () => void;
+}) => {
+  const { t } = useTranslation();
+  const latexId = useId();
+  const previewId = useId();
+  const latexInputRef = useRef<HTMLTextAreaElement>(null);
+  const [kind, setKind] = useState<MathFormulaKind>(draft?.kind ?? "inline");
+  const [latex, setLatex] = useState(draft?.latex ?? "");
+  const [error, setError] = useState<string | null>(null);
+  const editing = typeof draft?.pos === "number";
+
+  useEffect(() => {
+    if (!open) return;
+    setKind(draft?.kind ?? "inline");
+    setLatex(draft?.latex ?? "");
+    setError(null);
+    const timer = window.setTimeout(() => {
+      latexInputRef.current?.focus();
+      latexInputRef.current?.select();
+    }, 0);
+    return () => window.clearTimeout(timer);
+  }, [draft, open]);
+
+  const previewHtml = useMemo(() => renderPreviewHtml(latex, kind), [kind, latex]);
+
+  const submit = () => {
+    if (!latex.trim()) {
+      setError(t("mathFormulaDialog.errorEmpty"));
+      return;
+    }
+    onApply({
+      kind,
+      latex,
+      pos: draft?.pos,
+      from: draft?.from,
+      to: draft?.to,
+    });
+    onOpenChange(false);
+  };
+
+  return (
+    <Dialog open={open} onOpenChange={onOpenChange}>
+      <DialogContent className="max-w-lg gap-0 overflow-hidden p-0">
+        <DialogHeader className="border-b border-slate-200 px-5 py-5 pr-12 text-left">
+          <DialogTitle className="flex items-center gap-2 text-base">
+            <Sigma className="h-5 w-5 text-emerald-600" />
+            {editing ? t("mathFormulaDialog.editTitle") : t("mathFormulaDialog.title")}
+          </DialogTitle>
+          <DialogDescription className="pt-1 leading-5">
+            {t("mathFormulaDialog.description")}
+          </DialogDescription>
+        </DialogHeader>
+
+        <form
+          className="space-y-4 px-5 py-4"
+          onSubmit={(event) => {
+            event.preventDefault();
+            submit();
+          }}
+        >
+          {!editing && (
+            <div className="flex rounded-md border border-slate-200 p-0.5">
+              {(["inline", "block"] as const).map((value) => (
+                <button
+                  key={value}
+                  type="button"
+                  className={
+                    kind === value
+                      ? "flex-1 rounded-sm bg-emerald-50 px-3 py-1.5 text-xs font-medium text-emerald-800"
+                      : "flex-1 rounded-sm px-3 py-1.5 text-xs font-medium text-slate-600 hover:bg-slate-50"
+                  }
+                  aria-pressed={kind === value}
+                  onClick={() => setKind(value)}
+                >
+                  {value === "inline" ? t("mathFormulaDialog.inline") : t("mathFormulaDialog.block")}
+                </button>
+              ))}
+            </div>
+          )}
+
+          <div className="space-y-1.5">
+            <label htmlFor={latexId} className="text-xs font-medium text-slate-600">
+              {t("mathFormulaDialog.latexLabel")}
+            </label>
+            <textarea
+              ref={latexInputRef}
+              id={latexId}
+              value={latex}
+              rows={3}
+              spellCheck={false}
+              className="w-full resize-y rounded-md border border-slate-200 bg-card px-3 py-2 font-mono text-sm text-slate-900 outline-none ring-emerald-500/30 placeholder:text-slate-400 focus:border-emerald-400 focus:ring-2"
+              placeholder={t("mathFormulaDialog.latexPlaceholder")}
+              aria-invalid={Boolean(error) || undefined}
+              onChange={(event) => {
+                setLatex(event.target.value);
+                if (error) setError(null);
+              }}
+            />
+          </div>
+
+          <div className="space-y-1.5">
+            <p id={previewId} className="text-xs font-medium text-slate-600">
+              {t("mathFormulaDialog.preview")}
+            </p>
+            <div
+              aria-labelledby={previewId}
+              className={
+                kind === "block"
+                  ? "min-h-16 overflow-x-auto rounded-md border border-slate-200 bg-slate-50 px-3 py-4 text-center"
+                  : "min-h-12 overflow-x-auto rounded-md border border-slate-200 bg-slate-50 px-3 py-3"
+              }
+            >
+              {latex.trim() ? (
+                previewHtml ? (
+                  <span dangerouslySetInnerHTML={{ __html: previewHtml }} />
+                ) : (
+                  <p className="text-sm text-rose-700">{t("mathFormulaDialog.previewError")}</p>
+                )
+              ) : (
+                <p className="text-sm text-slate-400">{t("mathFormulaDialog.previewEmpty")}</p>
+              )}
+            </div>
+          </div>
+
+          {error && (
+            <p className="text-xs text-rose-600" role="alert">
+              {error}
+            </p>
+          )}
+
+          <DialogFooter className="gap-2 border-t border-slate-100 pt-4 sm:justify-between">
+            <div className="flex min-w-0 flex-1 flex-wrap gap-2">
+              {editing && onRemove && (
+                <Button
+                  type="button"
+                  variant="ghost"
+                  className="text-rose-700 hover:bg-rose-50 hover:text-rose-800"
+                  onClick={() => {
+                    onRemove();
+                    onOpenChange(false);
+                  }}
+                >
+                  {t("mathFormulaDialog.remove")}
+                </Button>
+              )}
+            </div>
+            <div className="flex flex-wrap justify-end gap-2">
+              <Button type="button" variant="ghost" onClick={() => onOpenChange(false)}>
+                {t("common.cancel")}
+              </Button>
+              <Button type="submit" variant="solid">
+                {t("mathFormulaDialog.apply")}
+              </Button>
+            </div>
+          </DialogFooter>
+        </form>
+      </DialogContent>
+    </Dialog>
+  );
+};
diff --git a/apps/web/src/components/editor/EditorBlockDragHandle.tsx b/apps/web/src/components/editor/EditorBlockDragHandle.tsx
new file mode 100644
index 00000000..570c4b20
--- /dev/null
+++ b/apps/web/src/components/editor/EditorBlockDragHandle.tsx
@@ -0,0 +1,47 @@
+import { useEffect } from "react";
+import type { Editor } from "@tiptap/react";
+import DragHandle from "@tiptap/extension-drag-handle-react";
+import { GripVertical } from "lucide-react";
+import { useTranslation } from "react-i18next";
+
+const BLOCK_DRAG_HANDLE_CLASS_NAME = "edgeever-block-drag-handle";
+
+const isBlockDragHandleEvent = (event: DragEvent) => {
+  const target = event.target;
+  return target instanceof Element && Boolean(target.closest(`.${BLOCK_DRAG_HANDLE_CLASS_NAME}`));
+};
+
+/** TipTap clears dataTransfer during dragstart; Chrome then refuses the drop unless a type remains. */
+const retainBlockDragDataTransfer = (event: DragEvent) => {
+  if (!isBlockDragHandleEvent(event) || !event.dataTransfer) {
+    return;
+  }
+  event.dataTransfer.effectAllowed = "move";
+  if (![...event.dataTransfer.types].includes("text/plain")) {
+    event.dataTransfer.setData("text/plain", " ");
+  }
+};
+
+export const EditorBlockDragHandle = ({ editor }: { editor: Editor }) => {
+  const { t } = useTranslation();
+
+  useEffect(() => {
+    document.addEventListener("dragstart", retainBlockDragDataTransfer);
+    return () => document.removeEventListener("dragstart", retainBlockDragDataTransfer);
+  }, []);
+
+  if (editor.isDestroyed || !editor.isEditable) {
+    return null;
+  }
+
+  return (
+    <DragHandle
+      editor={editor}
+      className={BLOCK_DRAG_HANDLE_CLASS_NAME}
+      nested
+    >
+      <span className="sr-only">{t("editor.dragHandle")}</span>
+      <GripVertical aria-hidden="true" className="h-4 w-4" />
+    </DragHandle>
+  );
+};
diff --git a/apps/web/src/components/editor/SlashCommandMenu.test.mjs b/apps/web/src/components/editor/SlashCommandMenu.test.mjs
index 7271b979..563f6ecd 100644
--- a/apps/web/src/components/editor/SlashCommandMenu.test.mjs
+++ b/apps/web/src/components/editor/SlashCommandMenu.test.mjs
@@ -29,6 +29,8 @@ const labels = {
     divider: "分割线",
     fold: "折叠块",
     table: "表格",
+    "inline-math": "插入公式",
+    "block-math": "块级公式",
     "current-date": "当前日期",
     "current-time": "当前时间",
     "current-date-time": "当前日期和时间",
@@ -45,7 +47,7 @@ describe("slash command menu", () => {
     const unfilteredItems = filterSlashCommandItems(items, "");
     const heading6Index = unfilteredItems.findIndex((item) => item.id === "heading-6");
 
-    expect(unfilteredItems).toHaveLength(22);
+    expect(unfilteredItems).toHaveLength(24);
     expect(unfilteredItems.slice(heading6Index + 1, heading6Index + 4).map((item) => item.id)).toEqual([
       "current-date",
       "current-time",
@@ -83,6 +85,8 @@ describe("slash command menu", () => {
       "divider",
       "fold",
       "table",
+      "math",
+      "equation",
       "upload",
       "note",
       "link",
@@ -93,6 +97,8 @@ describe("slash command menu", () => {
     expect(filterSlashCommandItems(items, "collapse").map((item) => item.id)).toEqual(["fold"]);
     expect(filterSlashCommandItems(items, "table").map((item) => item.id)).toEqual(["table"]);
     expect(filterSlashCommandItems(items, "task").map((item) => item.id)).toEqual(["task-list"]);
+    expect(filterSlashCommandItems(items, "公式").map((item) => item.id)).toEqual(["inline-math", "block-math"]);
+    expect(filterSlashCommandItems(items, "equation").map((item) => item.id)).toEqual(["block-math"]);
   });
 
   test("formats local date and time as stable static text", () => {
diff --git a/apps/web/src/components/editor/SlashCommandMenu.tsx b/apps/web/src/components/editor/SlashCommandMenu.tsx
index 56bdc262..bc5d1d20 100644
--- a/apps/web/src/components/editor/SlashCommandMenu.tsx
+++ b/apps/web/src/components/editor/SlashCommandMenu.tsx
@@ -24,6 +24,7 @@ import {
   ListTodo,
   Pilcrow,
   Quote,
+  Sigma,
   Table2,
 } from "lucide-react";
 import {
@@ -53,6 +54,8 @@ export type SlashCommandId =
   | "divider"
   | "fold"
   | "table"
+  | "inline-math"
+  | "block-math"
   | "current-date"
   | "current-time"
   | "current-date-time"
@@ -76,6 +79,7 @@ export type SlashCommandActions = {
   openAttachmentPicker: () => void;
   openExternalLinkPicker: () => void;
   openNoteLinkPicker: () => void;
+  openMathFormula: (kind: "inline" | "block") => void;
 };
 
 export type SlashCommandItem = {
@@ -120,6 +124,8 @@ export const createSlashCommandItems = (labels: SlashCommandLabels): SlashComman
   { id: "divider", command: "divider", group: "insert", icon: BetweenHorizontalStart, label: labels.items.divider, keywords: ["rule", "分割", "分隔"] },
   { id: "fold", command: "fold", group: "insert", icon: ChevronsDownUp, label: labels.items.fold, keywords: ["collapse", "spoiler", "折叠", "折りたたみ"] },
   { id: "table", command: "table", group: "insert", icon: Table2, label: labels.items.table, keywords: ["表格"] },
+  { id: "inline-math", command: "math", group: "insert", icon: Sigma, label: labels.items["inline-math"], keywords: ["latex", "formula", "katex", "公式", "数学", "数式"] },
+  { id: "block-math", command: "equation", group: "insert", icon: Sigma, label: labels.items["block-math"], keywords: ["latex", "formula", "display", "katex", "块级公式", "独立公式", "数式"] },
   { id: "attachment", command: "upload", group: "insert", icon: FileUp, label: labels.items.attachment, keywords: ["file", "attachment", "文件", "上传", "附件"] },
   { id: "note-link", command: "note", group: "insert", icon: Link, label: labels.items["note-link"], keywords: ["link", "memo", "笔记", "引用"] },
   { id: "external-link", command: "link", group: "insert", icon: Link, label: labels.items["external-link"], keywords: ["url", "web", "链接", "网址"] },
@@ -248,6 +254,14 @@ const runSlashCommand = ({
     case "divider": chain.setHorizontalRule().run(); break;
     case "fold": chain.setDetails().run(); break;
     case "table": chain.insertTable({ rows: 3, cols: 3, withHeaderRow: true }).run(); break;
+    case "inline-math":
+      chain.run();
+      window.requestAnimationFrame(() => actions.openMathFormula("inline"));
+      break;
+    case "block-math":
+      chain.run();
+      window.requestAnimationFrame(() => actions.openMathFormula("block"));
+      break;
     case "current-date": chain.insertContent(formatCurrentDate(new Date())).run(); break;
     case "current-time": chain.insertContent(formatCurrentTime(new Date())).run(); break;
     case "current-date-time": chain.insertContent(formatCurrentDateTime(new Date())).run(); break;
diff --git a/apps/web/src/components/editor/editor-pane-helpers.test.mjs b/apps/web/src/components/editor/editor-pane-helpers.test.mjs
index 83f950aa..784e84e8 100644
--- a/apps/web/src/components/editor/editor-pane-helpers.test.mjs
+++ b/apps/web/src/components/editor/editor-pane-helpers.test.mjs
@@ -1,6 +1,9 @@
 import { describe, expect, test } from "bun:test";
 import { readFileSync } from "node:fs";
-import { shouldRetryCreatedMemoFocus } from "./editor-pane-helpers.ts";
+import {
+  shouldInsertDroppedResourceFiles,
+  shouldRetryCreatedMemoFocus,
+} from "./editor-pane-helpers.ts";
 
 describe("created memo focus retry", () => {
   test("keeps retrying until the editor is hydrated, editable, and focused", () => {
@@ -56,3 +59,32 @@ describe("editor document reset", () => {
     expect(source).toContain("plugins: editor.state.plugins");
   });
 });
+
+describe("dropped resource files", () => {
+  const fileTransfer = {
+    items: [{ kind: "file", getAsFile: () => new File(["png"], "preview.png", { type: "image/png" }) }],
+    files: [],
+  };
+
+  test("inserts clipboard or OS files", () => {
+    expect(shouldInsertDroppedResourceFiles({
+      dataTransfer: fileTransfer,
+      isInternalNodeDrag: false,
+    })).toBe(true);
+  });
+
+  test("does not steal a block-handle drop that Chrome tagged with a preview file", () => {
+    expect(shouldInsertDroppedResourceFiles({
+      dataTransfer: fileTransfer,
+      isInternalNodeDrag: true,
+    })).toBe(false);
+  });
+});
+
+describe("block handle drop wiring", () => {
+  test("lets ProseMirror finish an internal node drag", () => {
+    const source = readFileSync(new URL("../EditorPane.tsx", import.meta.url), "utf8");
+    expect(source).toContain("shouldInsertDroppedResourceFiles");
+    expect(source).toContain("isInternalNodeDrag: Boolean(view.dragging)");
+  });
+});
diff --git a/apps/web/src/components/editor/editor-pane-helpers.ts b/apps/web/src/components/editor/editor-pane-helpers.ts
index d60c7866..767feda7 100644
--- a/apps/web/src/components/editor/editor-pane-helpers.ts
+++ b/apps/web/src/components/editor/editor-pane-helpers.ts
@@ -188,6 +188,15 @@ export const getResourceFilesFromDataTransfer = (dataTransfer: DataTransfer | nu
   return files.filter((file) => file.size > 0);
 };
 
+/** Block-handle drags set view.dragging; Chrome may also attach a preview image as a file. */
+export const shouldInsertDroppedResourceFiles = ({
+  dataTransfer,
+  isInternalNodeDrag,
+}: {
+  dataTransfer: DataTransfer | null;
+  isInternalNodeDrag: boolean;
+}) => !isInternalNodeDrag && getResourceFilesFromDataTransfer(dataTransfer).length > 0;
+
 export const syncStatusToSaveState = (status: "pending" | "syncing" | "conflict" | "error") => {
   if (status === "conflict") {
     return "conflict";
diff --git a/apps/web/src/components/editor/math-formula.test.mjs b/apps/web/src/components/editor/math-formula.test.mjs
new file mode 100644
index 00000000..ee20fcb8
--- /dev/null
+++ b/apps/web/src/components/editor/math-formula.test.mjs
@@ -0,0 +1,90 @@
+import { describe, expect, test } from "bun:test";
+import { Editor } from "@tiptap/core";
+import { createEdgeEverDocumentExtensions } from "@edgeever/shared";
+import { createEdgeEverMathematics } from "@edgeever/shared/mathematics";
+import {
+  applyMathFormula,
+  deleteMathFormula,
+  resolveMathFormulaTarget,
+  selectedTextAsLatex,
+} from "./math-formula.ts";
+
+const createEditor = (content) => new Editor({
+  extensions: createEdgeEverDocumentExtensions({
+    mathematics: createEdgeEverMathematics(),
+  }),
+  content,
+});
+
+describe("math formula commands", () => {
+  test("inserts inline math at the caret", () => {
+    const editor = createEditor({
+      type: "doc",
+      content: [{ type: "paragraph", content: [{ type: "text", text: "ab" }] }],
+    });
+    editor.commands.setTextSelection(2);
+    expect(applyMathFormula(editor, { kind: "inline", latex: "x^2" })).toBe(true);
+    expect(editor.getJSON().content[0].content).toEqual([
+      { type: "text", text: "a" },
+      { type: "inlineMath", attrs: { latex: "x^2" } },
+      { type: "text", text: "b" },
+    ]);
+    editor.destroy();
+  });
+
+  test("replaces the selected text with inline math", () => {
+    const editor = createEditor({
+      type: "doc",
+      content: [{ type: "paragraph", content: [{ type: "text", text: "E=mc^2" }] }],
+    });
+    editor.commands.setTextSelection({ from: 1, to: 7 });
+    expect(selectedTextAsLatex(editor)).toBe("E=mc^2");
+    expect(applyMathFormula(editor, {
+      kind: "inline",
+      latex: "E=mc^2",
+      from: 1,
+      to: 7,
+    })).toBe(true);
+    expect(editor.getJSON().content[0].content).toEqual([
+      { type: "inlineMath", attrs: { latex: "E=mc^2" } },
+    ]);
+    editor.destroy();
+  });
+
+  test("updates and deletes an existing formula", () => {
+    const editor = createEditor({
+      type: "doc",
+      content: [{
+        type: "paragraph",
+        content: [{ type: "inlineMath", attrs: { latex: "a+b" } }],
+      }],
+    });
+    editor.commands.setTextSelection(1);
+    const target = resolveMathFormulaTarget(editor, 1);
+    expect(target).toEqual({ kind: "inline", pos: 1, latex: "a+b" });
+    expect(applyMathFormula(editor, { kind: "inline", latex: "c+d", pos: 1 })).toBe(true);
+    expect(editor.getJSON().content[0].content[0].attrs.latex).toBe("c+d");
+    expect(deleteMathFormula(editor, { kind: "inline", pos: 1 })).toBe(true);
+    expect(editor.getJSON().content[0].content ?? []).toEqual([]);
+    editor.destroy();
+  });
+
+  test("inserts a display formula as its own block", () => {
+    const editor = createEditor({
+      type: "doc",
+      content: [{ type: "paragraph" }],
+    });
+    expect(applyMathFormula(editor, { kind: "block", latex: "\\int x dx" })).toBe(true);
+    expect(editor.getJSON().content.some((node) => node.type === "blockMath" && node.attrs.latex === "\\int x dx")).toBe(true);
+    editor.destroy();
+  });
+
+  test("rejects empty latex", () => {
+    const editor = createEditor({
+      type: "doc",
+      content: [{ type: "paragraph" }],
+    });
+    expect(applyMathFormula(editor, { kind: "inline", latex: "  " })).toBe(false);
+    editor.destroy();
+  });
+});
diff --git a/apps/web/src/components/editor/math-formula.ts b/apps/web/src/components/editor/math-formula.ts
new file mode 100644
index 00000000..e9075200
--- /dev/null
+++ b/apps/web/src/components/editor/math-formula.ts
@@ -0,0 +1,64 @@
+import type { Editor } from "@tiptap/core";
+import {
+  BLOCK_MATH_NODE_TYPE,
+  INLINE_MATH_NODE_TYPE,
+} from "@edgeever/shared/mathematics";
+
+export type MathFormulaKind = "inline" | "block";
+
+export type MathFormulaTarget = {
+  kind: MathFormulaKind;
+  latex: string;
+  pos: number;
+};
+
+export type MathFormulaDraft = {
+  kind: MathFormulaKind;
+  latex: string;
+  pos?: number;
+  from?: number;
+  to?: number;
+};
+
+export const selectedTextAsLatex = (editor: Editor) =>
+  editor.state.doc.textBetween(editor.state.selection.from, editor.state.selection.to, " ").trim();
+
+export const resolveMathFormulaTarget = (editor: Editor, pos?: number): MathFormulaTarget | null => {
+  const documentPos = pos ?? editor.state.selection.from;
+  const node = editor.state.doc.nodeAt(documentPos);
+  if (!node) return null;
+  if (node.type.name === INLINE_MATH_NODE_TYPE) {
+    return { kind: "inline", pos: documentPos, latex: String(node.attrs.latex ?? "") };
+  }
+  if (node.type.name === BLOCK_MATH_NODE_TYPE) {
+    return { kind: "block", pos: documentPos, latex: String(node.attrs.latex ?? "") };
+  }
+  return null;
+};
+
+export const applyMathFormula = (editor: Editor, draft: MathFormulaDraft) => {
+  const latex = draft.latex.trim();
+  if (!latex) return false;
+
+  if (typeof draft.pos === "number") {
+    return draft.kind === "inline"
+      ? editor.commands.updateInlineMath({ latex, pos: draft.pos })
+      : editor.commands.updateBlockMath({ latex, pos: draft.pos });
+  }
+
+  const from = draft.from ?? editor.state.selection.from;
+  const to = draft.to ?? editor.state.selection.to;
+  const chain = editor.chain();
+  if (to > from) {
+    chain.deleteRange({ from, to });
+  }
+  return draft.kind === "inline"
+    ? chain.insertInlineMath({ latex, pos: from }).run()
+    : chain.insertBlockMath({ latex, pos: from }).run();
+};
+
+export const deleteMathFormula = (editor: Editor, target: Pick<MathFormulaTarget, "kind" | "pos">) => {
+  return target.kind === "inline"
+    ? editor.commands.deleteInlineMath({ pos: target.pos })
+    : editor.commands.deleteBlockMath({ pos: target.pos });
+};
diff --git a/apps/web/src/styles/globals.css b/apps/web/src/styles/globals.css
index ac8d22eb..f992551c 100644
--- a/apps/web/src/styles/globals.css
+++ b/apps/web/src/styles/globals.css
@@ -88,7 +88,12 @@ html.dark[data-edgeever-environment="demo"] body::after {
 }
 
 .ProseMirror .tiptap-mathematics-render--editable {
-  cursor: text;
+  cursor: pointer;
+  border-radius: 0.2rem;
+}
+
+.ProseMirror .tiptap-mathematics-render--editable:hover {
+  background: rgb(22 160 110 / 0.08);
 }
 
 .ProseMirror .inline-math-error,
@@ -697,6 +702,54 @@ textarea {
   font-feature-settings: "chws" 1;
 }
 
+.edgeever-block-drag-handle {
+  z-index: 20;
+  display: none;
+  width: 1.25rem;
+  height: 1.5rem;
+  align-items: center;
+  justify-content: center;
+  cursor: grab;
+  border-radius: 0.25rem;
+  color: #94a3b8;
+}
+
+.edgeever-block-drag-handle:hover {
+  background: #f1f5f9;
+  color: #16a06e;
+}
+
+.edgeever-block-drag-handle:active,
+.edgeever-block-drag-handle[data-dragging="true"] {
+  cursor: grabbing;
+}
+
+@media (min-width: 1024px) {
+  .edgeever-block-drag-handle {
+    display: flex;
+  }
+}
+
+.ProseMirror-selectednoderange {
+  border-radius: 0.25rem;
+  background: rgb(22 160 110 / 0.06);
+  outline: 2px solid rgb(22 160 110 / 0.28);
+}
+
+:root.dark .edgeever-block-drag-handle {
+  color: #64748b;
+}
+
+:root.dark .edgeever-block-drag-handle:hover {
+  background: #1e293b;
+  color: #34d399;
+}
+
+:root.dark .ProseMirror-selectednoderange {
+  background: rgb(52 211 153 / 0.1);
+  outline-color: rgb(52 211 153 / 0.35);
+}
+
 .ProseMirror [data-type="details"] {
   display: flex;
   align-items: flex-start;
diff --git a/bun.lock b/bun.lock
index 59e08043..952ac78f 100644
--- a/bun.lock
+++ b/bun.lock
@@ -25,15 +25,20 @@
         "@tanstack/react-query": "latest",
         "@tanstack/react-virtual": "^3.14.13",
         "@tiptap/core": "3.31.0",
+        "@tiptap/extension-collaboration": "3.31.0",
         "@tiptap/extension-details": "3.31.0",
+        "@tiptap/extension-drag-handle": "3.31.0",
+        "@tiptap/extension-drag-handle-react": "3.31.0",
         "@tiptap/extension-image": "3.31.0",
         "@tiptap/extension-list": "3.31.0",
+        "@tiptap/extension-node-range": "3.31.0",
         "@tiptap/extension-placeholder": "3.31.0",
         "@tiptap/extension-table": "3.31.0",
         "@tiptap/pm": "3.31.0",
         "@tiptap/react": "3.31.0",
         "@tiptap/starter-kit": "3.31.0",
         "@tiptap/suggestion": "3.31.0",
+        "@tiptap/y-tiptap": "3.0.7",
         "ai": "^7.0.58",
         "aws4fetch": "^1.0.20",
         "class-variance-authority": "latest",
@@ -97,7 +102,7 @@
     },
     "apps/desktop": {
       "name": "@edgeever/desktop",
-      "version": "1.78.1",
+      "version": "1.79.0",
       "dependencies": {
         "@edgeever/public-network": "workspace:*",
         "croner": "^10.0.1",
@@ -1377,10 +1382,16 @@
 
     "@tiptap/extension-code-block-lowlight": ["@tiptap/extension-code-block-lowlight@3.31.0", "", { "peerDependencies": { "@tiptap/core": "3.31.0", "@tiptap/extension-code-block": "3.31.0", "@tiptap/pm": "3.31.0", "highlight.js": "^11", "lowlight": "^2 || ^3" } }, "sha512-fFwXqwh0CwJkQzdqgv4ObcS70m0Muq1RbAZUTQNZFqCDcu1krDJW0PWNmua7+nZdmXwOyA2PDUTAtWYFQ+srpw=="],
 
+    "@tiptap/extension-collaboration": ["@tiptap/extension-collaboration@3.31.0", "", { "peerDependencies": { "@tiptap/core": "3.31.0", "@tiptap/pm": "3.31.0", "@tiptap/y-tiptap": "^3.0.7", "yjs": "^13" } }, "sha512-VkfOhXOVK6YJx2vHrDTuaoSt9kQK1QVjpnbe2svU57fDtY3z7pUxdulzgk9ntQ7/6mjyhODugmOm0UuQKYwBxA=="],
+
     "@tiptap/extension-details": ["@tiptap/extension-details@3.31.0", "", { "peerDependencies": { "@tiptap/core": "3.31.0", "@tiptap/extension-text-style": "3.31.0", "@tiptap/pm": "3.31.0" } }, "sha512-j1ZDrXRPPvCoOrKrVV1e2BXFpHVsHYmikr2ORtI0+gDh/+4qruqrm7ftGic2lm77B2hzKtm2adoSSi9XL6UQew=="],
 
     "@tiptap/extension-document": ["@tiptap/extension-document@3.31.0", "", { "peerDependencies": { "@tiptap/core": "3.31.0" } }, "sha512-C2eDFoBlcRAb4sgbc9ZH+mrFFbjIS9VyoERGeDum3QRdqLEKU1h14Th7isHpGQzTvTywhXQxqXC64mgeSGXLsA=="],
 
+    "@tiptap/extension-drag-handle": ["@tiptap/extension-drag-handle@3.31.0", "", { "dependencies": { "@floating-ui/dom": "^1.6.13" }, "peerDependencies": { "@tiptap/core": "3.31.0", "@tiptap/extension-collaboration": "3.31.0", "@tiptap/extension-node-range": "3.31.0", "@tiptap/pm": "3.31.0", "@tiptap/y-tiptap": "^3.0.7" } }, "sha512-v04z6nHLGaxC0EYJ6hhWzsl01LfuiMLseTXYEqls5nnl0nmYntPBiwHX2ZoHJ5e42qi76nVO2G06fyigUsI10w=="],
+
+    "@tiptap/extension-drag-handle-react": ["@tiptap/extension-drag-handle-react@3.31.0", "", { "peerDependencies": { "@tiptap/extension-drag-handle": "3.31.0", "@tiptap/pm": "3.31.0", "@tiptap/react": "3.31.0", "react": "^16.8 || ^17 || ^18 || ^19", "react-dom": "^16.8 || ^17 || ^18 || ^19" } }, "sha512-sDAUF5HS0aytRjhbX+jnHzkD695W9Ha4B2SkOcpM1wDSmaYbTdgkwaFh2BZPkd+Hb/J2kdBgjR+ceZE9FU6R2Q=="],
+
     "@tiptap/extension-dropcursor": ["@tiptap/extension-dropcursor@3.31.0", "", { "peerDependencies": { "@tiptap/extensions": "3.31.0" } }, "sha512-hIZOPfM0sGkAhPV69IK1zWMbWBd3wmhS0XCKBRcXUWrE2MW4kkaSyYprSFqtqFuUa3lVIEFrlME1WOEBJ2/2rg=="],
 
     "@tiptap/extension-floating-menu": ["@tiptap/extension-floating-menu@3.31.0", "", { "peerDependencies": { "@floating-ui/dom": "^1.0.0", "@tiptap/core": "3.31.0", "@tiptap/pm": "3.31.0" } }, "sha512-NFwv1Kah3zGLmjj53Z+pA2584GdgMDClgvebJPqSunsSdHwHlFwfu+Op1u73xuEYOd6wGgCgzzDZ3V4CKwkJqg=="],
@@ -1407,6 +1418,8 @@
 
     "@tiptap/extension-mathematics": ["@tiptap/extension-mathematics@3.31.0", "", { "peerDependencies": { "@tiptap/core": "3.31.0", "@tiptap/pm": "3.31.0", "katex": "^0.16.4 || ^0.17.0 || ^0.18.0" } }, "sha512-wr3L8zb/jGWPeYb7xvn5AUqUz/ORR6V/kFRGqmZwdM45ksU2txt06Jj16eu5uiUDdGIcLgx0QiMw6hgUyJZAQg=="],
 
+    "@tiptap/extension-node-range": ["@tiptap/extension-node-range@3.31.0", "", { "peerDependencies": { "@tiptap/core": "3.31.0", "@tiptap/pm": "3.31.0" } }, "sha512-QiBWWVdnmQHMKRKrN4UySUaqqTK2jjqZL6Jtz6xFzrrZYI/iS91Uf0J6g4NaM6dfm+8ODUBL8m7aHeYbGZam6A=="],
+
     "@tiptap/extension-ordered-list": ["@tiptap/extension-ordered-list@3.31.0", "", { "peerDependencies": { "@tiptap/extension-list": "3.31.0" } }, "sha512-KLCax7pI/3JTCkMY01n2+CXwZRPPsIVR1fvSmkFMryUPonkkMYWSUlXCuYKvF22+kM0gU0kiXsVjqsn/YFdeDg=="],
 
     "@tiptap/extension-paragraph": ["@tiptap/extension-paragraph@3.31.0", "", { "peerDependencies": { "@tiptap/core": "3.31.0" } }, "sha512-78l9D/jpKvvWXrBBzYPfgqwonBY76+1MMgSovkPffIbya+jaYDJdZhIpeCZXtSBDnw8cYE/rheAeusN1QG3SVQ=="],
@@ -1435,6 +1448,8 @@
 
     "@tiptap/suggestion": ["@tiptap/suggestion@3.31.0", "", { "peerDependencies": { "@floating-ui/dom": "^1.0.0", "@tiptap/core": "3.31.0", "@tiptap/pm": "3.31.0" } }, "sha512-p/m8K4jmF+b5JdRcZ5onOKxJf3dsTcXhnV6qAjDu1xrvpY8lXZe4DXgtuAUvh5Q4Msmq6IYuMAvleR4WAkIXIQ=="],
 
+    "@tiptap/y-tiptap": ["@tiptap/y-tiptap@3.0.7", "", { "dependencies": { "lib0": "^0.2.100" }, "peerDependencies": { "prosemirror-model": "^1.7.1", "prosemirror-state": "^1.2.3", "prosemirror-view": "^1.9.10", "y-protocols": "^1.0.1", "yjs": "^13.5.38" } }, "sha512-3VG01F7i2JDghWsBZSBKi7ypMiN5UVVSyD18IwoXx7ilm0ZynrTS+XNpmgxfuiSBjdauWk7tUlP04xfM8Bw4Vw=="],
+
     "@trickfilm400/rollup-plugin-off-main-thread": ["@trickfilm400/rollup-plugin-off-main-thread@3.0.0-pre1", "", { "dependencies": { "ejs": "^3.1.10", "json5": "^2.2.3", "magic-string": "^0.30.21", "string.prototype.matchall": "^4.0.12" } }, "sha512-/67zpWDBLV+oYAEL682s1ktXL0HgqX76f6gaVGkGnVZlBbm1zd0v4Bz8MFF2GGhoX9rvfq3KSQHubFHwa6w6/Q=="],
 
     "@tybys/wasm-util": ["@tybys/wasm-util@0.10.3", "", { "dependencies": { "tslib": "^2.4.0" } }, "sha512-F3fo1MYrRJYL3zER0OUOmkutjr1Vp23m7OsSgp7nq4SP6OqX6C/56XFIPAl5bt3zaBRjmW7SGz3u/6LwFpYcOg=="],
@@ -2791,6 +2806,8 @@
 
     "isexe": ["isexe@3.1.5", "", {}, "sha512-6B3tLtFqtQS4ekarvLVMZ+X+VlvQekbe4taUkf/rhVO3d/h0M2rfARm/pXLcPEsjjMsFgrFgSrhQIxcSVrBz8w=="],
 
+    "isomorphic.js": ["isomorphic.js@0.2.5", "", {}, "sha512-PIeMbHqMt4DnUP3MA/Flc0HElYjMXArsw1qwJZcm9sqR8mq3l8NYizFMty0pWwE/tzIGH3EKK5+jes5mAr85yw=="],
+
     "jackspeak": ["jackspeak@4.2.3", "", { "dependencies": { "@isaacs/cliui": "^9.0.0" } }, "sha512-ykkVRwrYvFm1nb2AJfKKYPr0emF6IiXDYUaFx4Zn9ZuIH7MrzEZ3sD5RlqGXNRpHtvUHJyOnCEFxOlNDtGo7wg=="],
 
     "jake": ["jake@10.9.4", "", { "dependencies": { "async": "^3.2.6", "filelist": "^1.0.4", "picocolors": "^1.1.1" }, "bin": { "jake": "bin/cli.js" } }, "sha512-wpHYzhxiVQL+IV05BLE2Xn34zW1S223hvjtqk0+gsPrwd/8JNLXJgZZM/iPFsYc1xyphF+6M6EvdE5E9MBGkDA=="],
@@ -2875,6 +2892,8 @@
 
     "levn": ["levn@0.4.1", "", { "dependencies": { "prelude-ls": "^1.2.1", "type-check": "~0.4.0" } }, "sha512-+bT2uH4E5LGE7h/n3evcS/sQlJXCpIp6ym8OWJ5eV6+67Dsql/LaaT7qJBAt2rzfoa/5QBGBhxDix1dMt2kQKQ=="],
 
+    "lib0": ["lib0@0.2.117", "", { "dependencies": { "isomorphic.js": "^0.2.4" }, "bin": { "0serve": "bin/0serve.js", "0gentesthtml": "bin/gentesthtml.js", "0ecdsa-generate-keypair": "bin/0ecdsa-generate-keypair.js" } }, "sha512-DeXj9X5xDCjgKLU/7RR+/HQEVzuuEUiwldwOGsHK/sfAfELGWEyTcf0x+uOvCvK3O2zPmZePXWL85vtia6GyZw=="],
+
     "lie": ["lie@3.3.0", "", { "dependencies": { "immediate": "~3.0.5" } }, "sha512-UaiMJzeWRlEujzAuw5LokY1L5ecNQYZKfmyZ9L7wDHb/p5etKaxXhohBcrw0EYby+G/NA52vRSN4N39dxHAIwQ=="],
 
     "lighthouse-logger": ["lighthouse-logger@2.0.2", "", { "dependencies": { "debug": "^4.4.1", "marky": "^1.2.2" } }, "sha512-vWl2+u5jgOQuZR55Z1WM0XDdrJT6mzMP8zHUct7xTlWhuQs+eV0g+QL0RQdFjT54zVmbhLCP8vIVpy1wGn/gCg=="],
@@ -4169,6 +4188,8 @@
 
     "xxhash-wasm": ["xxhash-wasm@1.1.0", "", {}, "sha512-147y/6YNh+tlp6nd/2pWq38i9h6mz/EuQ6njIrmW8D1BS5nCqs0P6DG+m6zTGnNz5I+uhZ0SHxBs9BsPrwcKDA=="],
 
+    "y-protocols": ["y-protocols@1.0.7", "", { "dependencies": { "lib0": "^0.2.85" }, "peerDependencies": { "yjs": "^13.0.0" } }, "sha512-YSVsLoXxO67J6eE/nV4AtFtT3QEotZf5sK5BHxFBXso7VDUT3Tx07IfA6hsu5Q5OmBdMkQVmFZ9QOA7fikWvnw=="],
+
     "y18n": ["y18n@5.0.8", "", {}, "sha512-0pfFzegeDWJHJIAmTLRP2DwHjdF5s7jo9tuztdQxAhINCdvS+3nGINqPd00AphqJR/0LhANUS6/+7SCb98YOfA=="],
 
     "yallist": ["yallist@5.0.0", "", {}, "sha512-YgvUTfwqyc7UXVMrB+SImsVYSmTS8X/tSrtdNZMImM+n7+QTriRXyXim0mBrTXNeqzVF0KWGgHPeiyViFFrNDw=="],
@@ -4185,6 +4206,8 @@
 
     "yet-another-react-lightbox": ["yet-another-react-lightbox@3.32.0", "", { "peerDependencies": { "@types/react": "^16 || ^17 || ^18 || ^19", "@types/react-dom": "^16 || ^17 || ^18 || ^19", "react": "^16.8.0 || ^17 || ^18 || ^19", "react-dom": "^16.8.0 || ^17 || ^18 || ^19" }, "optionalPeers": ["@types/react", "@types/react-dom"] }, "sha512-FWODOMrE07i3O5MeWRcYlcnAUk518zkUYKAe307pVW5pkey3hKMcAIWn8yMIURzGvbd3m9eghWO9CocEZmQPIg=="],
 
+    "yjs": ["yjs@13.6.32", "", { "dependencies": { "lib0": "^0.2.99" } }, "sha512-lfiJIIC4Xayt5ItynE407ehlE03pCjeOc4hkR4yxxvvNJ4kuiN25B0g+Qp8XagYz361LLL7DCzR5bvFJ81QKtQ=="],
+
     "yocto-queue": ["yocto-queue@1.2.2", "", {}, "sha512-4LCcse/U2MHZ63HAJVE+v71o7yOdIe4cZ70Wpf8D/IyjDKYQLV5GD46B+hSTjJsvV5PztjvHoU580EftxjDZFQ=="],
 
     "yocto-spinner": ["yocto-spinner@0.2.3", "", { "dependencies": { "yoctocolors": "^2.1.1" } }, "sha512-sqBChb33loEnkoXte1bLg45bEBsOP9N1kzQh5JZNKj/0rik4zAPTNSAVPj3uQAdc6slYJ0Ksc403G2XgxsJQFQ=="],
diff --git a/package.json b/package.json
index dda7d345..5a6626b5 100644
--- a/package.json
+++ b/package.json
@@ -137,15 +137,20 @@
     "@tanstack/react-query": "latest",
     "@tanstack/react-virtual": "^3.14.13",
     "@tiptap/core": "3.31.0",
+    "@tiptap/extension-collaboration": "3.31.0",
     "@tiptap/extension-details": "3.31.0",
+    "@tiptap/extension-drag-handle": "3.31.0",
+    "@tiptap/extension-drag-handle-react": "3.31.0",
     "@tiptap/extension-image": "3.31.0",
     "@tiptap/extension-list": "3.31.0",
+    "@tiptap/extension-node-range": "3.31.0",
     "@tiptap/extension-placeholder": "3.31.0",
     "@tiptap/extension-table": "3.31.0",
     "@tiptap/pm": "3.31.0",
     "@tiptap/react": "3.31.0",
     "@tiptap/starter-kit": "3.31.0",
     "@tiptap/suggestion": "3.31.0",
+    "@tiptap/y-tiptap": "3.0.7",
     "ai": "^7.0.58",
     "aws4fetch": "^1.0.20",
     "class-variance-authority": "latest",
diff --git a/packages/shared/src/i18n/en-US.ts b/packages/shared/src/i18n/en-US.ts
index b78e8b47..7a6ea9ac 100644
--- a/packages/shared/src/i18n/en-US.ts
+++ b/packages/shared/src/i18n/en-US.ts
@@ -1657,6 +1657,7 @@ export const enUS = {
     },
     placeholder: "space for AI · / commands · @ notes",
     placeholderCommands: "/ commands · @ notes",
+    dragHandle: "Drag block",
     noteBodyAria: "Note body",
     markdownSourceAria: "Markdown source",
     loading: "Loading",
@@ -1956,6 +1957,8 @@ export const enUS = {
     mermaidZoomOut: "Zoom out diagram",
     mermaidResetZoom: "Reset diagram zoom",
     mermaidCloseViewer: "Close diagram viewer",
+    math: "Insert formula",
+    blockMath: "Display formula",
     horizontalRule: "Divider",
     themeBlock: "Insert content block",
     deleteThemeBlock: "Delete themed block",
@@ -2000,6 +2003,21 @@ export const enUS = {
     errorInvalid: "Enter a valid URL, such as example.com or https://example.com.",
     errorUnsupported: "This URL scheme is not allowed.",
   },
+  mathFormulaDialog: {
+    title: "Insert formula",
+    editTitle: "Edit formula",
+    description: "Write the formula in LaTeX. Inline math sits in a sentence; a display formula gets its own line.",
+    inline: "Inline",
+    block: "Display",
+    latexLabel: "LaTeX",
+    latexPlaceholder: "E = mc^2",
+    preview: "Preview",
+    previewEmpty: "Preview appears after you enter LaTeX",
+    previewError: "Could not render this formula",
+    apply: "Apply",
+    remove: "Delete formula",
+    errorEmpty: "Enter LaTeX.",
+  },
   noteLinkPicker: {
     title: "Link a note",
     searchPlaceholder: "Search notes to link",
diff --git a/packages/shared/src/i18n/ja.ts b/packages/shared/src/i18n/ja.ts
index e26954aa..ce3ca24e 100644
--- a/packages/shared/src/i18n/ja.ts
+++ b/packages/shared/src/i18n/ja.ts
@@ -1657,6 +1657,7 @@ export const ja = {
     },
     placeholder: "スペースで AI · / コマンド · @ ノート",
     placeholderCommands: "/ コマンド · @ ノート",
+    dragHandle: "ブロックをドラッグ",
     noteBodyAria: "ノート本文",
     markdownSourceAria: "Markdown ソース",
     loading: "読み込み中",
@@ -1956,6 +1957,8 @@ export const ja = {
     mermaidZoomOut: "図を縮小",
     mermaidResetZoom: "図のズームをリセット",
     mermaidCloseViewer: "図ビューアを閉じる",
+    math: "数式を挿入",
+    blockMath: "ブロック数式",
     horizontalRule: "区切り線",
     themeBlock: "コンテンツブロックを挿入",
     deleteThemeBlock: "テーマ付きブロックを削除",
@@ -2000,6 +2003,21 @@ export const ja = {
     errorInvalid: "example.com または https://example.com のような有効な URL を入力してください。",
     errorUnsupported: "この URL スキームは使えません。",
   },
+  mathFormulaDialog: {
+    title: "数式を挿入",
+    editTitle: "数式を編集",
+    description: "LaTeX で数式を書きます。インラインは文中に入り、ブロックは独立した行になります。",
+    inline: "インライン",
+    block: "ブロック",
+    latexLabel: "LaTeX",
+    latexPlaceholder: "E = mc^2",
+    preview: "プレビュー",
+    previewEmpty: "LaTeX を入力するとプレビューされます",
+    previewError: "この数式を表示できません",
+    apply: "適用",
+    remove: "数式を削除",
+    errorEmpty: "LaTeX を入力してください。",
+  },
   noteLinkPicker: {
     title: "ノートをリンク",
     searchPlaceholder: "リンクするノートを検索",
diff --git a/packages/shared/src/i18n/zh-CN.ts b/packages/shared/src/i18n/zh-CN.ts
index cf404733..df715421 100644
--- a/packages/shared/src/i18n/zh-CN.ts
+++ b/packages/shared/src/i18n/zh-CN.ts
@@ -1657,6 +1657,7 @@ export const zhCN = {
     },
     placeholder: "空格唤起 AI · / 命令 · @ 引用",
     placeholderCommands: "/ 命令 · @ 引用",
+    dragHandle: "拖动块",
     noteBodyAria: "笔记正文",
     markdownSourceAria: "Markdown 源码",
     loading: "加载中",
@@ -1954,6 +1955,8 @@ export const zhCN = {
     mermaidZoomOut: "缩小图表",
     mermaidResetZoom: "重置图表缩放",
     mermaidCloseViewer: "关闭图表查看器",
+    math: "插入公式",
+    blockMath: "块级公式",
     horizontalRule: "分割线",
     themeBlock: "插入内容块",
     deleteThemeBlock: "删除主题化组件",
@@ -1998,6 +2001,21 @@ export const zhCN = {
     errorInvalid: "请输入有效网址，例如 example.com 或 https://example.com。",
     errorUnsupported: "不支持此网址协议。",
   },
+  mathFormulaDialog: {
+    title: "插入公式",
+    editTitle: "编辑公式",
+    description: "用 LaTeX 编写公式。行内公式会出现在句子中，块级公式单独占一行。",
+    inline: "行内",
+    block: "块级",
+    latexLabel: "LaTeX",
+    latexPlaceholder: "E = mc^2",
+    preview: "预览",
+    previewEmpty: "输入 LaTeX 后显示预览",
+    previewError: "无法渲染该公式",
+    apply: "应用",
+    remove: "删除公式",
+    errorEmpty: "请输入 LaTeX。",
+  },
   noteLinkPicker: {
     title: "引用笔记",
     searchPlaceholder: "搜索要引用的笔记",
diff --git a/packages/shared/src/mathematics.ts b/packages/shared/src/mathematics.ts
index 75c05d4b..694301ed 100644
--- a/packages/shared/src/mathematics.ts
+++ b/packages/shared/src/mathematics.ts
@@ -1,4 +1,5 @@
 import { BlockMath, InlineMath } from "@tiptap/extension-mathematics";
+import type { Node as ProseMirrorNode } from "@tiptap/pm/model";
 import {
   BLOCK_MATH_NODE_TYPE,
   edgeEverBlockMathMarkdownTokenizer,
@@ -11,6 +12,13 @@ export {
   INLINE_MATH_NODE_TYPE,
 } from "./mathematics-markdown";
 
+export type EdgeEverMathematicsClickHandler = (node: ProseMirrorNode, pos: number) => void;
+
+export type CreateEdgeEverMathematicsOptions = {
+  onInlineClick?: EdgeEverMathematicsClickHandler;
+  onBlockClick?: EdgeEverMathematicsClickHandler;
+};
+
 const EdgeEverInlineMath = InlineMath.extend({
   markdownTokenizer: edgeEverInlineMathMarkdownTokenizer,
 });
@@ -26,7 +34,7 @@ const katexOptions = {
 };
 
 /** Fresh extension instances for each TipTap editor or Markdown manager. */
-export const createEdgeEverMathematics = () => [
-  EdgeEverBlockMath.configure({ katexOptions }),
-  EdgeEverInlineMath.configure({ katexOptions }),
+export const createEdgeEverMathematics = (options: CreateEdgeEverMathematicsOptions = {}) => [
+  EdgeEverBlockMath.configure({ katexOptions, onClick: options.onBlockClick }),
+  EdgeEverInlineMath.configure({ katexOptions, onClick: options.onInlineClick }),
 ];