314996 2026-05-17 20:26:27 -0700 Avoid lazy-allocating UndoManager during Document teardown 2026-05-17 22:25:51 -0700 1 1 1 Unclassified WebKit DOM WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED InRadar P2 Normal --- 1 ddkilzer ddkilzer webkit-bug-importer oldest_to_newest 2211601 0 ddkilzer 2026-05-17 20:26:27 -0700 `Document::willBeRemovedFromFrame()` calls `protect(undoManager())->removeAllItems()` unconditionally. `Document::undoManager()` lazy-creates the `UndoManager` through `ensureUndoManager()` when `m_undoManager` is null. For clients that do not create `m_undoManager`, every detached `Document` lazy-allocates a 32-byte `UndoManager`, calls a no-op `removeAllItems()` on its empty `HashSet`, and then destroys it in `~Document`. This is wasted work that scales with every detached `Document`. 2211602 1 webkit-bug-importer 2026-05-17 20:26:36 -0700 <rdar://problem/177311258> 2211603 2 ddkilzer 2026-05-17 20:42:52 -0700 Pull request: https://github.com/WebKit/WebKit/pull/65083 2211628 3 ews-feeder 2026-05-17 22:25:49 -0700 Committed 313393@main (408429b44b24): <https://commits.webkit.org/313393@main> Reviewed commits have been landed. Closing PR #65083 and removing active labels.