Mouse Tester

Click the left button once at a normal pace, repeatedly. If the tester occasionally flags a double-click when you only pressed once, the button's switch is bouncing — a common wear failure that usually means the switch needs replacement.

The tester intentionally suppresses the context menu inside the test area so the right button can be tested like any other. Right-click behaves normally everywhere else.

Not necessarily. Some mice map side buttons through vendor software to keyboard shortcuts rather than standard mouse buttons 4 and 5, in which case the browser never sees them as mouse buttons. Check your mouse software's button mapping.

Yes — taps, physical clicks, and two-finger scrolling all generate the same events. Middle-click may require a three-finger tap depending on your touchpad settings.