This bug is for crash report bp-5b069f8c-7c1c-48d3-a797-6b9d10200729.

Top 10 frames of crashing thread:

0 libsystem_kernel.dylib libsystem_kernel.dylib@0x3c8a 
1 libmozglue.dylib mozilla::detail::ConditionVariableImpl::wait mozglue/misc/ConditionVariable_posix.cpp:108
2 XUL mozilla::TaskController::GetRunnableForMTTask xpcom/threads/TaskController.cpp:280
3 XUL nsThread::ProcessNextEvent xpcom/threads/nsThread.cpp:1148
4 XUL mozilla::ipc::MessagePump::Run ipc/glue/MessagePump.cpp:109
5 XUL MessageLoop::Run ipc/chromium/src/base/message_loop.cc:309
6 XUL nsBaseAppShell::Run widget/nsBaseAppShell.cpp:137
7 XUL nsAppShell::Run widget/cocoa/nsAppShell.mm:694
8 XUL XRE_RunAppShell toolkit/xre/nsEmbedFunctions.cpp:913
9 XUL MessageLoop::Run ipc/chromium/src/base/message_loop.cc:309

I think this is a dupe of whatever existing bug we have for GetRunnableForMTTask shutdown hangs. We just don't have symbols for whatever OSX version this is so the signature is junky. Hopefully that's on gsvelto or somebody else's radar already, but I'll needinfo him anyways.

macOS 10.16 is still in beta AFAIK and I don't think we can scrape symbols for betas but I might be wrong. I'm NI? Marco who should know.

We can scrape them manually, if we have a machine with that version.
Steven has been scraping symbols manually and sending them to me lately.

Just today I installed the current Big Sur beta (beta5). So yes, I can scrape its symbols. I'll send them to you, Marco.

I just finished scraping the symbols, and have sent them to Marco.

I used the gathersymbols.py script from https://github.com/marco-c/breakpad-scrape-system-symbols. But I had to overcome a couple of problems to get it working on BigSur, which I'll mention here for the record:

First, the script requires Python 2.7. But because Python 2.7 is officially EOL, Homebrew no longer allows you to install it. Fortunately there's a way around this: https://stackoverflow.com/questions/60650325/install-python2-on-a-mac-after-python-2-support-has-ended-on-homebrew. Afterwards you'll need to use pip to install the requests and futures libraries. (This is the reason you can't use Apple's own Python 2.7, which is missing these libraries.)

Second, because your copy of dump_syms will almost certainly be unsigned, BigSur will refuse to run it unless you do some handwaving. Install dump_syms to /usr/local/bin, then run it once from the command line, without any parameters. The OS will warn you that it's not properly signed, but will offer you a way to run it anyway.

(In reply to Steven Michaud [:smichaud] (Retired) from comment #5)

I just finished scraping the symbols, and have sent them to Marco.

And I've uploaded them to the symbol server. From now on, they'll have symbols (and you can reprocess crashes which were already processed if you want).

Big Sur crash reports still aren't getting fully symbolicated. I've opened bug 1661771.

Closing because no crashes reported for 12 weeks.