My laptop has a touchscreen (which I hardly ever use). I used my finger to remove a speck of dust from my screen (tapping an empty square in the process), and after that I was no longer able to click pieces with the actual mouse. Right clicking to draw arrows and highlight still worked, and the mouse worked for rearranging tabs, selecting the chat box, etc. I tried using my finger to move the pieces by touch, and that worked, but the mouse left-click didn't work for the rest of the game. A refresh after the game didn't fix the issue either. Loading the analysis board did re-enable the mouse though.
I suspect something is detecting touch input and disabling normal mouse control. If this is the case it should notify the user that this has happened and allow turning it back on (since touch input can easily happen by mistake).
I suspect something is detecting touch input and disabling normal mouse control. If this is the case it should notify the user that this has happened and allow turning it back on (since touch input can easily happen by mistake).