Like execute() but in the context of window {id}. The window will temporarily be made the current window, without triggering autocommands. When executing {command} autocommands will be triggered, this may have unexpected side effects. Use |:noautocmd| if needed. Example: call win_execute(winid, 'set syntax=python') Doing the same with setwinvar() would not trigger autocommands and not actually show syntax highlighting. Not all commands are allowed in popup windows. When window {id} does not exist then no error is given and an empty string is returned. Can also be used as a |method|, the base is passed as the second argument: GetCommand()->win_execute(winid)