You can help improve Thunderbird and other users - no prior experience is necessary. Below are just a few ways you can contribute to the Quality of Thunderbird.
These activities are simple, takes the least amount of time, and doesn't require any special skill.
Before Thunderbird is released to the general public, it goes through beta testing. To participate in this effort you'll need to run a Beta version which is different from the standard release version of Thunderbird. The Beta web page has advice and links to many helpful resources, including a beta topicbox group for advice and assistance.
While testing or searching bugzilla you might find some portions of Thunderbird that previously worked but do not work anymore. Bug reports will have the regression keyword.
For these bugs it is very helpful to know the "regression range", the 1-day range of changes that broke Thunderbird. A bug whose regression range has not been determined also has a bugzilla keyword regressionrange-wanted.
You can find the regression range using a wonderful semiautomated tool called mozregression, and hopefully identify the code which caused the regression behavior.
Bugs which are performance related, with the "perf" keyword, can be profiled using a tool which traces the code being used. This page has details on running the tool. More information to come.
Maintaining Thunderbird's bug reports
Bugzilla is the database / tool that tracks reported defects. Working in this area requires some experience using Thunderbird, and the ability to determine what the user reporting a problem might be seeing. You don't need great technical skill. It just takes a little time.
More information on this activity can be found here.
Daily build testing
This requires running Daily version which is different from the standard release version of Thunderbird. Daily is a difficult environment, because you get a new version almost every day, with updated code. Sometimes the daily build is broken by bugs. Otherwise, the challenges are similar to running a beta version. The daily topicbox group is available for advice and assistance.
Ask questions on Matrix
If you want to know more, ask in the Thunderbird support topic #thunderbird:mozilla.org on Matrix. Bear in mind volunteers may not respond immediately, so please be patient.
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