Crash report: https://crash-stats.mozilla.org/report/index/1b15bf17-119b-4b59-8efc-fe9fa0210810

MOZ_CRASH Reason: assertion failed: self.font_contexts.lock_shared_context().has_font(&font.font_key)

Top 10 frames of crashing thread:

0 libxul.so libxul.so@0x628cbd0 
1 libxul.so libxul.so@0x99a9fff 
2 libxul.so libxul.so@0x99a9fff 
3 libxul.so libxul.so@0x3e5932b 
4 libxul.so libxul.so@0x6a64213 
5 NotoSansCJK-Bold.ttc NotoSansCJK-Bold.ttc@0x506e053 
6 NotoSansCJK-Bold.ttc NotoSansCJK-Bold.ttc@0x6184572 
7 memfd:mozilla-ipc (deleted) memfd:mozilla-ipc @0x1a7165 
8 NotoSansCJK-Medium.ttc NotoSansCJK-Medium.ttc@0x1085572 
9 NotoSansCJK-Bold.ttc NotoSansCJK-Bold.ttc@0x15462d 

Affected versions

• 92.0b1
• 93.0a1

Affected platforms

• Ubuntu 16.04 x86

Steps to reproduce
Preconditions:

• a zh-CN locale build

1. Enable the search bar from about:preferences#search by clicking on ""Add search bar in toolbar"" option
2. Perform a search from the Search Bar

Expected result

• The search results page is opened

Actual result:

• The browser crashes

Regression range

• I will determine one asap

Other notes

• I can’t reproduce it on other platforms or Ubuntu version, but reproducible on a second machine with 16.04 version
• Using these steps the reproducibility is almost 100%
• Intermittently using different steps (by clicking a link from the History panel) I could reproduce the crash with the same signature with an en-US build
• Not sure what the right component should covered this, feel free to move to its corresponding one

Unfortunately the stack is useless here. But the crashing thread seems to be WRRenderBackend so I tentatively move it there.

I've searched manually for a regression range and ended up with the following pushlog. I hope it is a reliable one, since on earlier builds the crash reproducibility is pretty intermittent.

The pushlog range has software WR being enabled for some Linux machines, which looks like it could be relevant here. Andrew, can you please take a look to start?

Looks like the assert is this:

https://searchfox.org/mozilla-central/rev/d3683dbb252506400c71256ef3994cdbdfb71ada/gfx/wr/webrender/src/glyph_rasterizer/mod.rs#70

(In reply to Anca Soncutean [:Anca], Desktop Release QA from comment #0)

MOZ_CRASH Reason: assertion failed: self.font_contexts.lock_shared_context().has_font(&font.font_key)

Any reason not to dupe this to bug 1511493?

(In reply to Anca Soncutean [:Anca], Desktop Release QA from comment #0)

I'm getting the quite similar crash reports, as followings.
https://crash-stats.mozilla.org/report/index/c837f4f9-305f-4eb4-a22d-6a17c0210828
But, my notePC may looks to have trouble on hard disk drive hdd, very old one. How about yours.

Frame Module Signature Source Trust
Ø 0 libxul.so libxul.so@0x6650f80 context
Ø 1 libxul.so libxul.so@0x9b69fff scan
Ø 2 libxul.so libxul.so@0x9b69fff scan
Ø 3 libxul.so libxul.so@0x4eb06cc scan
Ø 4 NotoSansCJK-DemiLight.ttc NotoSansCJK-DemiLight.ttc@0x49fb053 scan
Ø 5 NotoSansCJK-Black.ttc NotoSansCJK-Black.ttc@0x48a3f68 scan
Ø 6 NotoSansCJK-Regular.ttc NotoSansCJK-Regular.ttc@0x3b75165 scan
Ø 7 NotoSansCJK-Black.ttc NotoSansCJK-Black.ttc@0x4563464 scan
Ø 8 NotoSansCJK-Bold.ttc NotoSansCJK-Bold.ttc@0x178a572 scan
Ø 9 NotoSansCJK-Regular.ttc NotoSansCJK-Regular.ttc@0x5bd562d scan
Ø 10 NotoSansCJK-DemiLight.ttc NotoSansCJK-DemiLight.ttc@0xa20f73 scan

(In reply to raycy.jp from comment #7)

(In reply to Anca Soncutean [:Anca], Desktop Release QA from comment #0)

I'm getting the quite similar crash reports, as followings. The new one.
https://crash-stats.mozilla.org/report/index/f8d15389-cc4e-4b73-b784-ea9c50210828

Frame Module Signature Source Trust
Ø 0 libxul.so libxul.so@0x6650f80 context
Ø 1 libxul.so libxul.so@0x9b69fff scan
Ø 2 libxul.so libxul.so@0x9b69fff scan
Ø 3 libxul.so libxul.so@0x4eb06cc scan
Ø 4 NotoSansCJK-Regular.ttc NotoSansCJK-Regular.ttc@0x1c5e165 scan
Ø 5 memfd:mozilla-ipc (deleted) memfd:mozilla-ipc (deleted)@0x6762d scan
Ø 6 NotoSansCJK-Bold.ttc NotoSansCJK-Bold.ttc@0x163346d scan
Ø 7 NotoSansCJK-Regular.ttc NotoSansCJK-Regular.ttc@0x18af373 scan
Ø 8 NotoSansCJK-Bold.ttc NotoSansCJK-Bold.ttc@0x4f8a36e scan
Ø 9 NotoSansCJK-Regular.ttc NotoSansCJK-Regular.ttc@0x87a872 scan
Ø 10 NotoSansCJK-Regular.ttc NotoSansCJK-Regular.ttc@0x55a464 scan
Ø 11 memfd:mozilla-ipc (deleted) memfd:mozilla-ipc (deleted)@0x382d scan
Ø 12 memfd:mozilla-ipc (deleted) memfd:mozilla-ipc (deleted)@0x6765e scan
Ø 13 NotoSansCJK-Thin.ttc NotoSansCJK-Thin.ttc@0x4ba4e6e scan
Ø 14 NotoSansCJK-Bold.ttc NotoSansCJK-Bold.ttc@0x2632b5e scan That's all.

And the new ones,
The recent crash reports sent,

bp-16959bae-8c58-4dce-b9c8-2aa350210828 2021/08/28 18:36
bp-0b292a5e-b705-4ab9-9963-b57130210828 2021/08/28 18:36
bp-01eca6ec-4c91-42f2-af49-58ea60210828 2021/08/28 18:36
bp-596dc0d9-c4ee-4e4c-9cbe-712c50210828 2021/08/28 18:36 ←　having similar pattern

(In reply to raycy.jp from comment #9)
I've set off most of add-ons not recomended, and firefox works so far.
Before this, I've tryed the chromium browser, it works without crash.
The trouble I am getting looks like not concerning with HDD trouble...

Among Some add-ons I've set off, there could be something...

(In reply to raycy.jp from comment #10)

Among Some add-ons I've set off, there could be something...

some add-ons

mouse dictionary
tab manager plus for firefox
table to excel
thefreedictionary.com lookup
hatena bookmark

(In reply to raycy.jp from comment #11)

some add-ons　of suspects remaining

tab manager plus for firefox
thefreedictionary.com lookup

or else...

(In reply to raycy.jp from comment #12)
some add-ons　of suspects remaining

tab manager plus for firefox
thefreedictionary.com lookup
Online Lab

or else...

(raycy.jp from bug 1729779 comment #23)

Got crash...
http://crash-stats.mozilla.com/report/index/bp-4feeebba-1306-483d-a3bb-bf1280210909

(raycy.jp from bug 1729779 comment #24)

(In reply to raycy.jp from comment #19)

Got crash, again... couldn't open the firefox history list popup...
http://crash-stats.mozilla.com/report/index/bp-1a773a3d-4965-4201-b00c-18c4d0210909

So, I've set both "gfx.webrender.all" and "gfx.webrender.allow-partial-present-buffer-age" change to "false", now.

Duping raycy.jp's font crashes to first report at bug 1720573.