Since we talk resizing windows, for months I was _sometimes_ unable to resize windows at all, and couldn't figure out why. I thought it was a random bug of macOS.
Finally I realized the issue: if a window spans across two displays, it won't resize. Insane!
(I have an external monitor up, laptop down, and it's easy to move a window such that it stretches a few pixels from monitor to the laptop. No resize for you!)
You can turn this off in the settings, forgot exactly where. I actually found after 1-2mo I preferred not being able to haha
Easy to stretch a few pixels? Easier to move windows with super+arrows so they snap perfectly to the monitor borders, and then you'd never have this issue. I rarely drag windows "by hand" (by mouse) anymore!