firefox add-ons and userscripts
an alternative keyboard layout (and QMK for a hardware implementation)
well and including historically: I learned programming through macromedia flash
It reminds me to stand up once an hour.
I do most of my homework on vs code, and use git to track and archive all my coding-related stuff to private repo. Seriously, it gives me peace of mind and euphoric joy when I finish my homework and push to the repo.
Internet browsers - almost any one.
GUI compilers / dev environment
I owe them pretty much everything.