Injections land on the surface first, so in a long session the plain
maxNodes tail window dropped their identity while their tokens kept
counting (sums cover the full surface) — the browser's inject section
showed a gray '0 items' row with a real token sum and no way to see
what was inside.
The served slice is now the newest maxNodes tail PLUS every live inject
node older than the tail (they are few; the concatenation stays
seq-ordered). droppedNodes and surfaceFloor count only the unserved
non-inject overflow, so the 'N earlier messages' note no longer
double-counts pinned injects, and per-step reconstruction sees them too.
Bowen Liang
beaa746409