Pre-cap, modificationHistory was an unbounded module-scoped array that
grew for every CSS edit through $B css across the entire session.
Small per-entry footprint but no upper bound, the kind of slow leak
that compounds over multi-day inspector use.
Cap is 200, oldest evicted on push past the cap. modHistoryTotalPushed
stays monotonic across the session so undoModification can tell the
user when their target index has been evicted, instead of just the
opaque pre-cap "No modification at index 500" with no context.
__testInternals export lets the cap + eviction error be unit-tested
without spinning up a CDP-driven Page. Production code must continue
to go through modifyStyle / undoModification / resetModifications.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Garry Tan