I've made a couple contributions to a program I use a lot (xournal++). I've got lots of personal projects though and setting up a dev environment is a bit of a hassle. I have heard docker can by useful for that though so I might look into that for the future.
Congrats! I am also using Linux 'fulltime'. I've been using computers since MSX and finally abandoned Windows as my primary OS in 2005. At work, I always keep a Windows machine around since we have an AD domain and have to keep supporting it, but Linux is great, even more so in the last 5 years when games are running 'almost' effortlessly.
If I can make a suggestion, check how you can contribute to your favorite distro. I've been helping out on Debian's pt-br translation team and it's very satisfying. I strongly recommend it!
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