If you want to help, a nice first step to get familiar with improving the system is to review Pull Requests.
For example, there are always very simple ones (like the ones listed here in "Cleanup Unused Variables”)
that are fairly easy to understand and review.
Open Pull requests are here: https://github.com/pharo-project/pharo/pulls
Added empty selection interval to force SpCodePresenter to auto-scroll. #8428
Inspecting a Text no longer shows the formatted text #8352
Fix broken tests - extract method and ocurrences #8420
RB - Add message to kwon how many occurrences were replaced #8380
Mouse events were sent twice when using an event handler #8404
Mouse over event is sent multiple times #8401
Improve the Help for Spec2 #8410
Fix a regression from earlier pharo that used to perserve order in sequences #8402
remove two unused ivars in GT-Tests #8432