None of them work as is, as they are intended to be used all at once.
You'll have to declare the variables in an another userstyle for the same domain as the userstyle(s) you are installing, so you don't lose them if the styles ever update. Example here.
If you wish to resize the sidebar(s) with a mouse, install this userscript.
Discord: class normalisation userscript
GitHub, SoundCloud: being logged in
Reddit: put the following in uBlock Origin's "My filters":
! reddit
!! no subreddit css
||thumbs.redditmedia.com$stylesheet,domain=old.reddit.com
!! no sticky header
old.reddit.com##+js(set-constant.js, isPinned, true)They all share the same style, and it depends on how you edited the variables above.
