in bug 1751492 we are running xpcshell tests with fission by default. They all have a message (extension left running at shutdown) in their errors

toolkit/components/extensions/test/xpcshell/xpcshell-common-e10s.ini

• test_ext_webRequest_filterResponseData.js
• test_ext_webRequest_viewsource_StreamFilter.js

toolkit/components/extensions/test/xpcshell/xpcshell-common.ini

• test_ext_cookieBehaviors.js
• test_ext_content_security_policy.js
• test_ext_contentscript_async_loading.js
• test_ext_contentscript_context.js
• test_ext_contentscript_context_isolation.js
• test_ext_contentscript_css.js
• test_ext_runtime_sendMessage.js
• test_ext_scripting_contentScripts_css.js
• test_ext_userScripts_register.js

toolkit/components/extensions/test/xpcshell/xpcshell-content.ini

• test_ext_contentscript_triggeringPrincipal.js
• test_ext_contentScripts_register.js
• test_ext_web_accessible_resources.js

For what it is worth, I tried looking at one of these failures, but I didn't really get anywhere because I'm not familiar with this code. Looking at test_ext_webRequest_viewsource_StreamFilter.js, it looked like in StreamFilter::Connect() the promise from the StreamFilterParent::Create() part of the code was getting rejected for some reason. I started messing with MozPromise logging to figure out why that was happening.

These started to fail after they got turned on for fission in bug 1751492.

https://hg.mozilla.org/mozilla-central/rev/006d2ee8b66e

The patch that landed just disabled a few more tests.

Closing because no crashes reported for 12 weeks.

This bug never got fixed. The bot just decided to add an invalid crash signature, then later closed the bug because the invalid crash signature wasn't happening.

The leave-open keyword is there and there is no activity for 6 months.
:zombie, maybe it's time to close this bug?
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