Conversation
send_frames_surface_tree descended into every subsurface and its overdue fallback fired for surfaces that never had a buffer. The renderer skips such surfaces and everything below them, so they are not presented. Firefox's WebRender compositor takes a frame callback as proof that its layer surface is presented: it never attaches the placeholder buffer that would map it, and the window stays black. Skip surfaces whose renderer state has no view, together with their children. Surfaces without renderer state keep the previous behaviour, so compositors that manage buffers themselves are unaffected. Developed with AI assistance (Claude Code, OpenAI Codex); all changes have been reviewed and are understood by the author.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Description
send_frames_surface_treesends frame callbacks to surfaces without a buffer, which the renderer never draws. Firefox withgfx.webrender.compositor.force-enabled=truetakes such a callback as proof its layer-root subsurface is presented, never attaches a buffer to it, and shows a black window.This skips surfaces whose renderer state has no view, together with their children. Surfaces without renderer state keep the old behaviour, and mapped but hidden surfaces still get the throttled fallback (unlike #2138).
AI assistance is disclosed in the commit message, per the AI policy.
Checklist