So imagine I have a spherecircle face divided into four identical slices. I want to uv unwrap them so they are all top of each other. I found one solution for blender 2.79 but it uses keyboard shortcuts that have changed for 2.8. I've also tried snapping but the islands are just super jittery and never even try to line up.
Install blender 2.79 from www.blender.org Open the preferences and go to the input tab. Change the pull down menu showing "name" to "key-binding". Enter the shortcut you used with blender 2.79. Go to the relevant part of the list ("UV Editor") and look up the name of the function, which is called by that shortcut. Remember that function namen. Exit blender 2.79. Start blender 2.80. Enter the preference dialog and select "keymap". Search for the function name (or a shorter version of its name. If the blender devs renamed it it will shurely be named similiar. Play with the function name a little bit.) Find the new short cut. And finally: Use that shortcut... ;)