What obscure about:config settings would you recommend changing?

pocket.enabled to false

First thing I do every clean install

Thanks! Just did this.
Thanks, I need to remember to do this tomorrow.

Just had to entirely do a fresh install like 6 hours ago.
- Hey buddy did u remember
What does it do?
- Disables the builtin Pocket extension.
I looked up "pocket.enabled" in about:config, but there wasn't an entry by that exact name. There was "extensions.pocket.enabled" though. Is that the same?

Setting full-screen-api.warning.timeout to 0 removes the notification at the top of the screen that tells you how to exit fullscreen mode.

For me:

browser.ctrlTab.recentlyUsedOrder: False

browser.tabs.insertAfterCurrent: True

dom.popup_maximum: 100

browser.download.improvements_to_download_panel: False

browser.tabs.insertAfterCurrent: True

I use this too. Great feature for tab hoarding keyboard warriors like me. Use Alt/Cmd + 9 to jump to the last tab.

dom.popup_maximum: 100

What does that do?

browser.download.improvements_to_download_panel: False

Why?
good stuff!

I always do the last one with browser.download.start_downloads_in_tmp_dir set to True
- I have my default Download dir set to /tmp anyways, which practically also makes the browser do that I believe.

browser.tabs.tabmanager.enabled -> false
It removes the tab manager. The down facing arrow next to the minimize button at the top right.

extensions.pocket.enabled -> false
Disable Pocket

identity.fxaccounts.enabled -> false
Disable Firefox account

media.autoplay.blocking_policy -> 2
You have to click the play button to play videos.

media.peerconnection.enabled -> false
Disable WebRTC

The firefox account is actually neat. It syncs bookmarks, history and passwords between desktop, phone, laptop or wherever you use firefox.
- I manually backup my bookmarks. Firefox is set to delete history when I close it. For passwords I use KeePassXC.
- It might still be useful to turn it off in some scenarios. For example you might not want firefox bothering you with the account on work PC where it might be against company policy to use the cloud sync.
Mention 5 obscure about:config params to change without explaining them

Refuse to elaborate
hello brother
What do browser.tabs.tabmanager.enabled and media.peerconnection.enabled do?
- media.peerconnection.enabled it disable WebRTC.
  
  browser.tabs.tabmanager.enabled it removes the tab manager. The down facing arrow next to the minimize button at the top right.
Why not set to 5 for media.autoplay.blocking_policy ?
- You have to click the play button to play the video. If you set it to 2.
  
  EDIT Here's a Mozilla wiki article about it.
  
  EDIT 2 You're talking about media.autoplay.default. That controls if autoplay is on or off and what is blocked, Audio only or Video & Audio.
media.autoplay.blocking_policy -> 2

This one breaks twitch for me. It doesn't let me unmute.
- Then enable auto play on twitch only. You can enable site by site and disable globally.

If you're lazy, librewolf is hardened firefox (sometimes it can break sites though)

browser.self_destruct_shortcut -> disabled

gets me everytime

What does this do?
- now when you press Ctrl+D it does not self destruct the computer

toolkit.legacyUserProfileCustomizations.stylesheets ⇾ True

to load CSS themes that make Firefox, your Firefox

Here a theme's collection https://firefoxcss-store.github.io/

I like resistFingerprinting = true but it may be a bit much for some people. You lose some keyboard hotkey capabilities in RES and all your windows always open at a certain size upon relaunch/new window.

I have a slow connection, so privacy.partition.network_state = false was a game changer. It prevents firefox to re-download an image (or video, or whatever) when you open it in a new tab (State Partitioning in Mozilla docs).

Warning: the main goal of State Partitioning is to prevent cross-site tracking, so this option will make that easier. In my case it's worth it and I mitigate that by other means, but you should be aware of it.

Not obscure but general.smoothScroll.msdPhysics.enabled=true is a must have IMO.

Sounds fancy. What does that do?
- You have to actually toggle to see it but IMO it massively improves how scrolling feels.
  
  There are a few more scrolling-related options out there on the net if there's a particular "feel" you want to go for. https://github.com/yokoffing/Betterfox/blob/main/Smoothfox.js provides a couple you can try out, and most of these custom scrolling options use msdPhysics as a baseline.
Very nice! Thanks for this!

dom.event.clipboardevents.enabled - block sites from preventing you using copy+paste e.g. in email and password fields.

I've only recently started using this one, so ask me again in a couple of months if it solves the issue :] or if it has unwanted side-effects - I know at least it doesn't prevent websites interacting with the clipboard entirely e.g. with a button to click to copy text to the clipboard

Backspace behavior: 1 something like that. Sets backspace to go to previous page it was once default but it is not anymore

Browsers changed this because people kept accidentally hitting it. I'm glad it's gone. My mouse has back/forward buttons on the side and I remapped those to go back and forward in browser history.
- Yeah i think someone might hit it accidentally i think it is a good decition to have it disabled by default but i still like it a lot and it is great to have a way to set it how i like it
Really, its gone? I think I still got the command that disables the back keybind in my user.js file. Now I can remove that line.
Note that you can use Ctrl/Cmd + [/] to navigate the tab history.

Have used this for a long time, one stop solution

I think you forgot to link something lol
- Or maybe they meant to reply to the arkenfox/user.js comment, but yeah.

I always like to start over with a clean slate. The one that's been with me for about 15 years now is browser.tabs.closeWindowWithLastTab set to false.

is there maybe a plugin that can remove all the moz shit mentioned here? i dont want to go through all comments. trimmedurls, pocket and actionbar...hate it.