Someone posted a shortcut you can add to JupyterLab here (<=== UPDATE: that link seems now dead). There’s an older tutorial doing the same thing here; however, the interface has changed quite a bit since then and so only use it as a guide. And a slightly newer step-by-step here. (Where at one time to look for other overrides was posted here. I don’t know if that is still where the typescript is found; however, it may help guide you to where to look around if you need to do additional, fancier things.)