How to reproduce:

1. Open attached project "858032-repro.zip"
2. Open "main" scene
3. Enter play mode
4. Right click on the scene: button "A" appears
5. Right click again: it disappears
6. Right click: two buttons "B" and "C" appears
7. Hover the mouse on button "C" and right click: it disappears
8. Right click again: button "A" appears

Expected behavior: button "A" is highlighted
Actual behavior: button "A" has no effect while hovering with mouse on

Note: It only happens if mouse is hovered on button "C" while right clicking (step 7)

Reproducible: 5.3.7p2, 5.4.3p3, 5.5.0p1, 5.6.0b1