yub VS firefox-scripts

Or make your own, right now, however you like: https://github.com/dohliam/yub. Can't advocate for this wonderful little html file enough.

I do! I missed the "web command-line" functionality so much I made a self-hosted replacement for it that can be run from a local file[0].

If you add it as your default search provider you can use it directly from the address bar, and at that point it works very similarly to DDG bang syntax (although it does a few other things apart from bookmarks as well).

[0]: https://github.com/dohliam/yub

For a long time, I've been making use of a MacOS-esque scrollbar I found online. I'm using XiaoXiaoFlood's loader script, and I've made the necessary changes to the files mentioned here to make it able to load .js and .uc.js files again. I've also modified the script a fair bit, though reverted most as it didn't work. Currently, I'm using this one, which has simply commented out the things that rely on Services. Though, even if I add it with something like const Services = globalThis.Services || ChromeUtils.import("resource://gre/modules/Services.jsm").Services; it doesn't make much of a difference. I've also tried using a userChrome.xml file, but that doesn't do much anymore. Was around 72/75 where that stopped working right?

Though for the full value I personally really also need some sort of interface that can show individual page visits in order to answer the question "What other pages did I visit at that point in time?" (sometimes I don't remember the right keywords to find a certain page again, but only some other page I visited during the same browsing session). The built-in history view is only of limited value here, because it always only shows the most-recent visit, so as soon as you visit a page again, it moves to the front of the list again and loses its original place and history context.

As usual, there used to be an add-on for that, which was subsequently broken by the move to webextensions (and even if somebody wanted to rewrite it, the webextension API doesn't cater for its full functionality). Thankfully some kind soul has maintained a version hacked to still work even on a current Firefox (https://github.com/xiaoxiaoflood/firefox-scripts/tree/master...).

This is what you're looking for.

Heads up though, it doesn't work for most tooltips. For that, I found the only way to change them is to use the above code in an agentsheet (https://github.com/xiaoxiaoflood/firefox-scripts, see the "StyloaiX" section)

Bootstrapped extensions are supported (really, xiaoxiaoflood is the only one who maintains any popular ones).

depending on your needs existing extensions may work for you, though the ContentScript based implementations have issues, if that's not enough you can use https://github.com/xiaoxiaoflood/firefox-scripts as it allows you to run the code in the browser UI, unfortunately there's no easy to use extension (and sadly FireGestures require update to work, even with loader injected into Quantum) so you may need to work with the code a bit (or more)

do what exactly? inject code? there are many slightly different approaches, the most reliable seems to be https://github.com/xiaoxiaoflood/firefox-scripts and using an approach like that forks can add extra configs to the UI making users' lives easier

Not in the foreseeable future, but maybe achievable with userChromeJS.