This bug is for crash report bp-5b136deb-5e44-48f8-9256-100a60200526.

Top 10 frames of crashing thread:

0 xul.dll RustMozCrash mozglue/static/rust/wrappers.cpp:16
1 xul.dll mozglue_static::panic_hook mozglue/static/rust/lib.rs:89
2 xul.dll core::ops::function::Fn::call<fn ../4fb7144ed159f94491249e86d5bbd033b5d60550/src/libcore/ops/function.rs:232
3 xul.dll std::panicking::rust_panic_with_hook ../4fb7144ed159f94491249e86d5bbd033b5d60550//src/libstd/panicking.rs:474
4 xul.dll std::panicking::begin_panic_handler ../4fb7144ed159f94491249e86d5bbd033b5d60550//src/libstd/panicking.rs:378
5 xul.dll core::panicking::panic_fmt ../4fb7144ed159f94491249e86d5bbd033b5d60550//src/libstd/panicking.rs:332
6 xul.dll core::panicking::panic ../4fb7144ed159f94491249e86d5bbd033b5d60550//src/libcore/panicking.rs:52
7 xul.dll webrender_api::resources::{{impl}}::get_font_data gfx/wr/webrender_api/src/resources.rs:49
8 xul.dll webrender_bindings::moz2d_renderer::{{impl}}::prepare_resources gfx/webrender_bindings/src/moz2d_renderer.rs:755
9 xul.dll webrender_api::resources::ApiResources::update gfx/wr/webrender_api/src/resources.rs:159

Reports start with Nightly build id 20200523092124. moz_crash_reason is called Option::unwrap() on a None value. The adapter values are

• adapter_device_id = 0x13c2
• adapter_driver_version = 26.21.14.4587
• adapter_subsys_id = 136619da
• adapter_vendor_id = 0x10de

Not sure if this is a defect in the driver.

Crashes started with build 20200523092124, the first build that contains bug 1639563 comment 14.

This looks to me to just be a different manifestation of bug 1640401. The fonts that fail to sanitize end up not getting added as font templates, so blob images end up seeing this downstream error. The gfxCriticalNotes I added in a follow-up patch should help point this out. In any case, the solution at the moment is to fix the actual sanitization problem, which is ongoing in bug 1640401.