P.S: This is stored locally and only works with TamperMonkey (and GreaseMonkey + forks probably). Maybe I can add an option to list all notes and import/export if it's usefull.
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Nice thing. Do you have a set of instruction to install it. I am not a good guy who tried browser extensions before. Still old school who does things manually LOL
How about good old bookmarks? Create a "notes on users" Folder, bookmark
the profile and Name it "This guy asked about keeping notes". When I visit your profile, there's a star in the address bar, and when I click it, I'm reminded you're the one who asked about keeping notes. You won't see it on posts, but you can easily find it back and it works on any site/browser without increased security risk.
This is a good example of old school LOL