If you’re using Mastodon on a Mac inside Fluid (https://fluidapp.com/) and you’ve paid for Fluid, you can add userstyles to change the UI.
I moved the tab bar to the side and remove some of the padding to make it feel closer to a proper app, styles are here: https://gist.github.com/rmlewisuk/c8ac28f431e23582053f813fc4ce5c16
Only thing I’m missing is using command+n to add a new Toot, but I’m not sure that’s possible because Fluid uses that for new window.
@rmlewisuk Maybe you can override with BetterTouchTool?
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