I'm using Linux Mint 19.1, and noticed that the shortcuts
alt+shift+down stopped working on Sublime Text 3. I checked the app configuration, and it is correct, so I suspect that this shortcut is being defined somewhere else (maybe by Cinnamon?), and want to find out if that's the case. But punching the shortcut aqpparently does nothing. I manually scanned the shortcut bindings at the keyboard preferences, and found nothing. Nut I'm not sure. I want to be certain that these shortcuts combinations are really unused by de OS.
So,l how can I find out what a given combination actually does? Notice that attempt the combination is not a good strategy, since the action may be something visually discrete, or may not even have any visual hint at all.