I'm looking for help 'cause I just got into this issue with Unity 2019.2.8f1 and I don't know how (if possible) to fix it.
I probably should mention that I upgraded this project from Unity 2019.1.0f2 and in that version, the animated materials preview was working fine. Now instead, the material itself works as expected when in Playmode, but it isn't animated at all when out of it. It only starts animating when the editor windows refresh, i.e. when I make some changes in some EditorWindows.
In case you were wondering I DID enable "Animated Materials" in the Scene window so that's not the issue.
I hope someone knows a solution to this issue. If it doesn't exist then thank you anyway for your time :)