This bug was filed from the Socorro interface and is report bp-09b0c9b4-fcd5-45dd-b96f-f3ad20181024. ============================================================= Top 10 frames of crashing thread: 0 libmozglue.dylib mozalloc_abort memory/mozalloc/mozalloc_abort.cpp:35 1 libmozglue.dylib abort memory/mozalloc/mozalloc_abort.cpp:82 2 XUL panic_abort::__rust_start_panic::abort src/libpanic_abort/lib.rs:61 3 XUL __rust_start_panic src/libpanic_abort/lib.rs:56 4 XUL std::panicking::rust_panic_with_hook src/libstd/panicking.rs:523 5 XUL std::panicking::begin_panic src/libstd/panicking.rs:409 6 XUL webrender::renderer::Renderer::draw_tile_frame gfx/webrender/src/tiling.rs:308 7 XUL webrender::renderer::Renderer::render_impl gfx/webrender/src/renderer.rs:2591 8 XUL wr_renderer_render gfx/webrender/src/renderer.rs:2476 9 XUL mozilla::wr::RenderThread::UpdateAndRender gfx/webrender_bindings/RendererOGL.cpp:146 ============================================================= Happened while scrolling a YouTube video page (in theater mode), on an late 2013 rMBP with integrated Iris graphics.

Socorro mentions bug 1442921 as related, but since that was fixed months ago, I assumed this was worth filing.

This is probably the same as bug 1501518. The fix is already on autoland.

Same here, will chime in if above-mentioned fix for bug 1501518 doesn't help. - https://crash-stats.mozilla.com/report/index/5ced5aa1-998f-4ac2-a565-b09c90181024 - https://crash-stats.mozilla.com/report/index/512b0053-2678-433a-bac8-b3dcd0181024 - https://crash-stats.mozilla.com/report/index/606e1711-9c12-42ce-94a6-c20670181024

There are 50 crashes (from 15 installations) in nightly 65 with buildid 20181024100114. In analyzing the backtrace, the regression may have been introduced by patch [1] to fix bug 1501319. [1] https://hg.mozilla.org/mozilla-central/rev?node=61b89032c551

I asked the sheriffs to merge the fix and spin another nightly so hopefully you'll be able to update to a non-crashing build soon.

The nightly channel should have a build with the fix now. Can you update and retest?

It happened with fullscreen videos on YouTube and is fixed with 20181024133237.

When I tried earlier, I wasn't able to reproduce this deterministically (in fact, I didn't reproduce it even once after the initial crash), so not sure I can help here.

Ok, seems like it should be safe to mark fixed. If anybody hits it again please let us know.

No crashes on 10-25 or later builds.