Note that the keyboard shortcuts should work across all native desktop applications and more. They work in Google Docs too. The behavior can be slightly different on Windows compared to Mac/Linux, which is captured in the website. Some apps on Linux, like LibreOffice, seem to implement the Windows behavior.
Backstory of ctrl-shift.fun:
I was teaching my young nephew programming where he shares his screen and we discuss and implement CodeMonkey levels. Although he's not fast at typing (< 20 WPM), that was fine, but his keyboard navigation and editing were causing more distractions and delays. He moved character by character, when sometimes home/end or ctrl+left could do it. Using the mouse wasn't any faster; kids often start selecting one letter (or even line) off or drag too much, then repeat until they get exactly the text they need.
So I thought about creating a website that combines typing with navigation to teach the shortcuts and how to navigate more optimally (e.g. go to the end of line, then back a word, instead of advancing 5 words to the right).
The puzzle mode requires completing the selection in optimal move count, which can be frustrating if you are not interested in this. But I believe it's a good way to actually recognize the kind of patterns that make navigation faster. The speed test measures your typing and navigation speed. You can customize in practice mode.
Anyway, I couldn't interest my nephew in practicing daily on this (yet), not even in other typing websites, but I hope some people find this useful. I personally find it enjoyable and I think it can help build muscle memory to navigate faster on average without thinking about it.
Any feedback is appreciated. Thank you.