Performance & crash fixes for chess.com#8546
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awesomekling wants to merge 7 commits intoLadybirdBrowser:masterfrom
Open
Performance & crash fixes for chess.com#8546awesomekling wants to merge 7 commits intoLadybirdBrowser:masterfrom
awesomekling wants to merge 7 commits intoLadybirdBrowser:masterfrom
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tcl3
reviewed
Mar 21, 2026
This is a normal spec-mandated early return, not an error condition. The already-started flag exists because prepare_script() is called from multiple paths (attribute changes, child insertions, DOM connection) and only the first call should proceed.
This is another normal spec early return in prepare_script(), not an error worth logging.
Instead of appending and re-sorting the entire records vector on every insert (O(n log n)), use binary search to find the correct insertion position and insert directly (O(log n) comparisons + O(n) shift).
Use AK::binary_search instead of a linear find_if scan in has_record_with_key(), taking advantage of the fact that records are kept sorted by key.
Since records are sorted by key, records matching a key range form a contiguous block. Use binary search to find the range boundaries and remove the block in one operation, instead of scanning every record with is_in_range().
Wrap the SerializationRecord (Vector<u8, 1024>) in an OwnPtr so that each ObjectStoreRecord is only ~16 bytes instead of ~1040+ bytes. This makes Vector operations on the records list dramatically cheaper since memmove now shifts pointers instead of kilobyte-sized buffers.
When a CSS animation keyframe uses var() referencing a nonexistent or invalid custom property, variable substitution produces a guaranteed-invalid value. The animation keyframe processing code did not handle this case, allowing the value to reach compute_opacity() (and similar functions) which would hit VERIFY_NOT_REACHED(). Fix this by skipping guaranteed-invalid values in compute_keyframe_values, matching how the regular cascading code treats them. This fixes a crash on chess.com.
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Three things here:
It's funny, I figured the sluggishness on chess.com was the chess engine, but it turns out it was just IndexedDB being inefficient 😅
(Although note that the chess engine is still slow, running as Wasm in the WebWorker process.)