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You can. GNOME has a JavaScript binding called gjs. It runs JavaScript (with SpiderMonkey) and has support for most of GNOME APIs.

What's stopping you then? If you can do it on your desktop, you can also do it on the Librem 5.

Does the IDE shown support it?

I have no idea - I'm using Qt Creator on my Librem 5. For TypeScript I guess you would probably like to run something like Atom or VSCode anyway.