Just found the project!
There is a cool readme that suggests searching for beginner issues, and provides great steps to get familiar with the project. The Beginner issue is from 2017 though and I’m unsure how to parse the state that the open Good First Issues are currently in from reading the comments.
Could someone explain which issue would be best for a first time OS contributor to attempt to tackle? Appreciate your time as I’m just starting to learn about Open Source contributing.
[original thread by Jonathan Schwob]
issues which are marked beginners should be good
we should use this label more often
usually finding some small bugs, writing test for them are good
you also can pick up some VS Code extensions which you like and test them: https://github.com/theia-ide/theia/wiki/Testing-VS-Code-extensions then report issues and looking into them, there are sometimes just missing commands which needs to be delegated to existing Theia commands, by doing it you will need to search/read code and build up code base knowledge 
I added the beginner label to the following issue as well if you’d like to tackle it https://github.com/theia-ide/theia/issues/4558
[Jonathan Schwob]
awesome, thank you. will take a look at these this week!