How to reproduce:
- Install Memory Profiler Package from Package manager (it's in preview)
- Open Memory Profiler from Window -> Analysis
- Press the "Load View..." button
- Close the resulting dialog whichever way you like

Actual on 2019.3:
"Load View..." stays impressed afterwards because it fired EditorGUIUtilites.ExitGUI()
Actual on 2018.3 - 2019.2:
"Load View..." stays looks impressed when hovering over it with the cursor.
Expected:
The Button returns to a normal state.