Send mouse event from GUI. Non-blocking: does not wait on any result, but queues the event to be processed soon by the event loop. Note: Currently this doesn't support "scripting" multiple mouse events by calling it multiple times in a loop: the intermediate mouse positions will be ignored. It should be used to implement real-time mouse input in a GUI. The deprecated pseudokey form ("<col,row>") of |nvim_input()| has the same limitation. Attributes: ~ {fast} Parameters: ~ {button} Mouse button: one of "left", "right", "middle", "wheel". {action} For ordinary buttons, one of "press", "drag", "release". For the wheel, one of "up", "down", "left", "right". {modifier} String of modifiers each represented by a single char. The same specifiers are used as for a key press, except that the "-" separator is optional, so "C-A-", "c-a" and "CA" can all be used to specify Ctrl+Alt+click. {grid} Grid number if the client uses |ui-multigrid|, else 0. {row} Mouse row-position (zero-based, like redraw events) {col} Mouse column-position (zero-based, like redraw events)