Red overlay on my canvas, whatever layer or folder selected (Windows 10)

[x3uu]

Hello,
I'm encountering the following issue: after exiting mask mode, I sometimes end up with that red overlay on my canvas (it seems to be applied to any layer or folder in my file). I can deactivate it by clicking outside the canvas and my file goes back to normal.

I checked if the quick mask feature was activated but it's not (and this would affect a single layer, not the full canvas).

I really have no idea where this red overlay comes from...

[gener7 · Accepted solution]

Your Layer Mask is in Rubylith mode separate from Quick Mask mode. Try the backslash \ key while the Layer mask is selected to shut it off.

Not many know that there is a separate Rubylith mode for masks.

[x3uu]

Thank you very much for your reply. Now it makes sense since I'm using the alt key to enter mask mode. I haven't tried the backslash key yet but I hope it'll help to exit the Rubylith mode (I'm using AZERTY keyboard)