ctrl+space mnemonic no longer working//ardour 4?

Earlier today, I could ctrl+space like in ardour 3 to stop recording and delete a track instead of saving it. Now, this no longer works and it leaves the track up (and saves it to disk) like I just pressed space. Is this a known issue or does anyone know of a setting I might have inadvertently changed to disable the use of ctrl+space or mnemonics in general?

In preferences, my keyboard layout is still menmonic-us. I wasn’t purposefully changing any settings at all that might have caused this, as I had everything set up properly the whole time. I tried restarting Ardour and now am at a loss.

I think you would just have to set the key binding yourself. Click Windows/Key Bindings, select the item that you want to set and press the key combination you want to use.

Try to re-assign the shortcut to establish that it’s really Ardour.

Most likely the Ctrl+Space never reaches Ardour in the first place because you “ibus” or the window-manager on your system captures it.
see also https://fedorahosted.org/fesco/ticket/798 https://wiki.gnome.org/Design/OS/KeyboardShortcuts

(OS X has a similar issue where Ctrl+Space triggers the spotlight search and ardour is non the wiser.)

There may actually be some issues with this. I hope to get them resolved soon.