Steps to reproduce:
Settings → Controls → Key Binds… → Debug → Set “Toggle Overlay” to a mouse input (ex: Mouse 3)
Go back to the game
Hit the mouse button chosen in step 1
Expected result:
F3 overlay opens
Actual result:
Nothing happens
Additional note:
Setting “Debug Modifier Key” to a mouse button and hitting a composite shortcut (ex: <Debug Modifier Key> + 1 to open the pie chart) does work and opens the F3 overlay correctly
Can confirm. When I set Debug Modifier Key to Button 4 (with Debug Options being F5). Mouse 4 + F5 can open the debug options but cannot close them; by contrast, the pie chart and graphs can be opened and closed with Mouse 4 + 1, Mouse 4 + 2, and Mouse 4 + 3 as expected.