i hate how hard it is to use modern software on tabby, my X61t thinkpad, just because modern ui is so damn big and bulky taking up unreasonable amount of space it doesn't need to on a 1024x768 screen. i have to jump through so many hoops...
one of my favourites is how mozilla showcased a new color picker for firefox mobile back in 2013, finally letting us pick any value instead of being limited to a random preset selection that serves nobody. that functionality has yet to come, 8 years later. https://blog.mozilla.org/ux/2013/12/a-new-colour-picker-on-firefox-for-android/
... to get fonts on all window renderer software in a single machine (gtk, qt, custom ones like firefox, etc) to agree to use much smaller fonts than they want to, so i can reclaim some usable screen real estate we perfectly had back in the early 2000s