Bug: Unsetting 'Activate Paste Stack' hotkey does not work

I can't unset the 'Activate Paste Stack' shortcut. It does change to 'None' after removing the shortcut, but if I go to another tab in the Settings window, and go back to the 'Shortcuts' tab, I can see the old shortcut again, as if changed werent saved. Also I tried contacting you instead of using this suggestion form, but the 'Get in touch' button on your contact page wasn't responding.