Input.GetMouseButtonUp returns true twice for one mouse click

Regardless of what I do, when I click the mouse in my Game scene, Input.GetMouseButtonUp(0) is returning true for two Update durations instead of just one (as expected, and as the docs imply). This creates issues because I’m trying to use this to determine if the mouse was clicked, but this feedback tells me that the mouse was clicked twice in two frames.

Am I doing something wrong here? I have a really basic scene so I can’t imagine I’ve introduced anything weird.

Are you reading Input.GetMouseButtonUp(0) in OnGUI or FixedUpdate? It must be read only in Update - these other functions may occur more than once in a single update cycle, and the Input.Get-Whatever-Down-Or-Up functions return true during the whole update cycle.

Erm is your computer low spec? that could be the problem… Or if you have a spare mouse anywhere try using that. Your mouse might be a bit faulty