From the 2026-07-11 expert review (finding F13/R3, P2): a single filter/mask/clip node nested >=2 levels below a RetainedContainer boundary disengages retention AND the GPU group transform for the ENTIRE subtree (all-or-nothing cliff, potentially thousands of nodes). Correct output, dev-warn exists, but one deep effect silently costs the whole optimization.
Goal: disengage only the offending sub-branch; keep retention + group transform for the rest of the group.
Refs: RetainedContainer._refreshBoundaryEngagement/_subtreeHasDeepBarrier; RenderNode._escapesTransformGroup. Classified 'Future' in the review roadmap.
From the 2026-07-11 expert review (finding F13/R3, P2): a single filter/mask/clip node nested >=2 levels below a RetainedContainer boundary disengages retention AND the GPU group transform for the ENTIRE subtree (all-or-nothing cliff, potentially thousands of nodes). Correct output, dev-warn exists, but one deep effect silently costs the whole optimization.
Goal: disengage only the offending sub-branch; keep retention + group transform for the rest of the group.
Refs: RetainedContainer._refreshBoundaryEngagement/_subtreeHasDeepBarrier; RenderNode._escapesTransformGroup. Classified 'Future' in the review roadmap.