Since upgrading to Big Sur from Mojave I noticed something strange and annoying on my 13 inch 2015 MBP. Moving windows or clicking buttons is really choppy, frames drop all the time when grabbing a window and moving the window around. It doesn't happen all the time, sometimes for a few seconds...
Model I have: MacBook Pro 2019 TouchBar 13 inch, 1.4Ghz (3.9Ghz boost clock), 8GB RAM, 256GB Storage. Running on Mac OS 10.14.6 (Latest version (excluding beta Catalina) as of writing)
Let the video do the description.
https://streamable.com/o4qqi - Chrome
https://streamable.com/o7m82 - Safari...