Mozilla Bug Tracker (Bugzilla)
What it does
Mozilla’s bug tracking system for Firefox and related projects. Covers browser bugs, web platform implementation work, DevTools, and standards-related tasks. Bugzilla is where Firefox engineers track feature implementation, regressions, and compat fixes. Web compat issues routed from webcompat.com often end up filed here.
Who is it for
Web developers reporting Firefox-specific bugs or checking the status of a known issue, Mozilla engineers and contributors triaging and resolving bugs, and web compat researchers tracking Firefox interoperability gaps.
Where to find it
Who is maintaining it
Mozilla, with contributions from the Firefox open-source community.