Defect Severity
Definition
We use the severity
field in Bugzilla to indicate the scope of a
bug’s effect on Firefox.
The field is display alongside the bug’s priority.
Values
Severity levels and their definitions are enumerated at https://wiki.mozilla.org/BMO/UserGuide/BugFields#bug_severity.
By default, new bugs have a severity of --
.
Examples of S1 bugs
WebExtensions disabled for all users
Web search not working from URL bar
Crashes with data loss
Examples of S2 bugs
Bugs that could reasonably be expected to cause a Firefox user to switch browsers, either because the severity is bad enough, or the frequency of occurrence is high enough.
Bug 1640441 - Slack hangs indefinitely in a onResize loop
Bug 1645651 - Changes in Reddit’s comment section JS code makes selecting text slow on Nightly
Bugs involving contractual partners (if not an S1)
Bugs reported from QA
Bug 1640913 - because an important message is not visible with the dark theme. It’s not marked as S1 since the issue is reproducible only on one OS and the functionality is not affected.
Bug 1641521 - because videos are not working on several sites with ETP on (default). This is not an S1 since turning ETP off fixes the issue.
Fuzzblocker bugs, which prevent fuzzing from making progress
Examples of S3 bugs
Bugs filed by contributors as part of daily refactoring and maintenance of the code base.
Bug 1634171 - Visual artifacts around circular images
Bugs reported from QA
Bug 1635105 because the associated steps to reproduce are uncommon, and the issue is no longer reproducible after refresh.
Bug 1636063 since it’s reproducible only on a specific web app, and only with a particular set of configurations.
Rules of thumb
The severity of most bugs of type
task
andenhancement
will beN/A
Do not assign bugs of type
defect
the severityN/A