This bug is for crash report bp-cef8dae1-079b-4f38-a76e-9a2f30190902.

Top 10 frames of crashing thread:

0 xul.dll GeckoCrash toolkit/xre/nsAppRunner.cpp:5097
1 xul.dll static void gkrust_shared::panic_hook toolkit/library/rust/shared/lib.rs:250
2 xul.dll static void core::ops::function::Fn::call<fn src/libcore/ops/function.rs:69
3 xul.dll static void std::panicking::rust_panic_with_hook src/libstd/panicking.rs:481
4 xul.dll static void std::panicking::continue_panic_fmt src/libstd/panicking.rs:384
5 xul.dll static void std::panicking::rust_begin_panic src/libstd/panicking.rs:311
6 xul.dll static void core::panicking::panic_fmt src/libcore/panicking.rs:85
7 xul.dll void core::panicking::panic src/libcore/panicking.rs:49
8 xul.dll static void webrender::batch::BatchBuilder::add_segmented_prim_to_batch gfx/wr/webrender/src/batch.rs:2605
9 xul.dll static void webrender::batch::BatchBuilder::add_prim_to_batch gfx/wr/webrender/src/batch.rs

This only appears in two installation in one of the latest nightlies, the raw crash reason is:

called Option::unwrap() on a None value

Looks like this is fixed now.

This is still happening on Nightly with the same crash reason.

Seems to be fixed.

Still happening on Nightly builds from a few days ago:
https://crash-stats.mozilla.org/report/index/1ee36e5c-1e07-494d-bdeb-047f80200502

I think the volume is still too low to warrant much investigation.

Volume is still low.