Real web composer: unclosed TeX

Linux Chromium 156.0.8078.4 · 1440×1000 · dark · no throttling
Three resets per case; six trusted keypresses per reset; paste from clipboard.

● Before 4d47d0b76e● After 7745667049

Unclosed inline TeX

Bare display openers

Case	Before ms	After ms	Speedup	Before: run medians ms	After: run medians ms
control × 1500	25.8	21.7	1.2×	33.2 / 21.5 / 24.6	21.5 / 21.1 / 22.2
inline × 250	377.8	48.7	7.7×	342.7 / 421 / 377.8	52.7 / 46.9 / 49.4
inline × 500	1,279.6	93.3	13.7×	1,222.2 / 1,262.4 / 1,436.2	100.8 / 89.7 / 93
inline × 1000	5,542	262	21.2×	5,381.3 / 5,726.5 / 5,567.1	264.2 / 274.2 / 261.4
inline × 1500	13,531.3	572.5	23.6×	13,641.1 / 13,038.9 / 13,957.1	558.1 / 586.2 / 595.5
display × 1000	5,665	195.5	29×	5,671 / 5,799.3 / 5,047	204.9 / 190.1 / 198.2
display × 1500	10,823.6	260.5	41.5×	11,964.3 / 10,736.3 / 10,248.2	260.9 / 269.9 / 250.8

Exact text and rendered content match across revisions: true
Every unclosed-TeX improvement exceeds both sides' run-median spread: true

Latency: DOM keydown → requestAnimationFrame → task after the rendering opportunity. Real app input, no parser microbenchmark. Video runs at original speed. All 42 resets retain the README mention and every character.