If I press a shortcut combination (such as Ctrl+M) – VS waits for the second one. What if I want to cancel it? (e.g. if I mistakenly press the wrong letter and am not sure which one.)
It just waits, with the "(Ctrl+M) was pressed. Waiting for a second key of chord..." in the bottom of the screen.
How do I cancel it?
Press Escape. Usually it is not tied as a second keystroke.
I normally press Esc .
I don't know of any keyboard shortcut where Esc is the second key press.
There aren't many visual studio Chords that end with Esc so just hit Esc it'll say The key combination is not a command but it prevents you from performing a valid chord.
Another option is to record a no-op macro and assign it to Ctrl-M, Esc. It will say running macro at the bottom quickly and go away.
You are in Dvorak Keyboard mode in windows. Press Ctrl+Shift to get out of it...