Got to know of them recently. They seem very cool.
Like, I don’t have to install anything extra.

https://www.freecodecamp.org/news/what-are-bookmarklets/
https://bk7312.github.io/bookmarklets/

I especially like this one that shows Id links. Useful while sharing wikipedia links:

https://github.com/madacol/web-automation/blob/master/bookmarklets/Id Linker.js
:::.

And this one which helps to use text fragments:

https://stackoverflow.com/questions/62989058/how-does-text-in-url-work-to-highlight-text#answer-76131511

Discliamer: Be careful with copy-pasting bookmarklets into your browser. Only do so if you trust it.

Which all bookmarklets do you use, find useful?
Please share them.

Are there similar easy things that most people sort of easily have access to? I think Libreoffice’s/Excel’s record macro function would be useful for people too.

Are there any communities for similar things, sort-of like beginner automation?

Thanks in advance.