System Information
Linux Mint 18.3 x64, nVidia GeForce GTX1070, using proprietary driver 384.130
Blender Version
Broken: blender-2.80-19a55b5a007-linux-glibc219-x86_64
Short description of error
When UI is set to "overlap regions" and a panel from a recent operation is visible, this panel will suddenly resize when changing an unrelated panel size (e.g. node editor). The resized panel will snap back to the correct size on mouse over.
Just watch this very short video for clarification: https://www.youtube.com/watch?v=aBFrpdyl6i8