How to replace the site code on someone else's site?

Question

css

Hello everyone, I need a little help I did it a long time ago, I don’t remember how you can replace the html (not css) code forever on someone else’s site? there are a bunch of extensions such as "stylish", etc. but they only change css, there is web override 1.3 and it seems like you can replace a piece of html code in it, but I don’t understand anything, tell me who can!

For example, you need to transfer the status in VK from the profile to the messages, or transfer the date of the messages from the messages to the full name, or your ideas, well, in general, just tell me who can do it, I saw another article about jquery that you can replace js with js but didn’t understand anything or didn’t want to , in general I will be glad to help!

Answer 1

If you just need to remove an annoying block from the site - better use uBlock Origin.
Well, if you edit the page for yourself and "forever" (not just styles) - TamperMonkey. There are both for chrome and firelis
https://www.tampermonkey.net/
You will need at least minimal knowledge of js
upd. Here are some templates to get you started https://gist.github.com/spiralx/2a8fa339b8b9f987de73