[Fixed] Tools | Magnet Mask | Select/Deselect not working

[dgud]

I'll record a video today night to show the problem to you, ok?

I don't know if that helps, I understand that it doesn't work for you I don't understand why.
Is anything printed in the log/console?

Could you please try the following?

-Reset and Select a couple of edge rings, mask them.
-Deselect all edges, Tools | Magnet Mask | Select
-And the masked edges from the mask is selected.

That works as expected, so it must be some difference between my config and yours.