Run the check
Test one button with deliberate single presses and record suspect intervals.
Repeat with a different double-click speed setting or vendor profile.
Try the same mouse in another application and on another computer.
Read the result
Repeated duplicates on one button across environments raise a switch hypothesis; one fast pair does not.
Limits and next step
A browser records delivered events, not the switch contacts or firmware debounce.
Repeat the check after changing one setting or connection. Keep a record of what changed before deciding whether the device needs service.