Found that the reason this was happening to me was because of a spellcheck plugin ( https://chrome.google.com/webstore/detail/webpage-spell-check/mgdhaoimpabdhmacaclbbjddhngchjik ). I've disabled it and my keyboard shortcuts are working again now.
We have had issues with keyboard shortcuts reported in the past, but we usually have a hard time reproducing them to be able to pinpoint exactly what the issue is.
Usually refreshing the page or restarting the Desktop app should get the shortcuts back to working again.
Do you mind sharing what is the version of the browser you are using, or if you are using the desktop app?