When your project only has one frame and you press Control+Delete, this ambiguous pop up appears -
@jan.cosmigo It may save some user confusion if this pop up explained itself or simply didn’t pop up (maybe an error sound if nothing else). I myself was momentarily confused why it was appearing until I figured out I was remembering the wrong shortcut for Frame > Clear, which is Control+Backspace.
Frame > Clear still has an arbitrary shortcut that you can’t remove/change. If you do try to change it, then it just has two shortcuts.
And if no shortcut is manually set, PMNG forgets to tell you it actually still has the default one (Control+Backspace):