It would be helpful if the mouseClick() method could accept key modifiers.
For example, Ctrl+Shift+Click could be served with one request.
You could simply toggle Ctrl & Shift keys using http://robotjs.io/docs/syntax#keytogglekey-down-modifier
You can write a callback function to do this with robot.keyToggle('right_shift', 'down').
I totally agree, but this would need to invoke more robotJS methods.
The issue I opened is not a bug, it's an enhancement request for sending only one call for multiple key and click combinations.
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You could simply toggle Ctrl & Shift keys using http://robotjs.io/docs/syntax#keytogglekey-down-modifier