Run multiple instances of an app on Mac OS X

Click Applications on Dock, select Automator. Choose Application. On searchbox, type: shell. Choose Run Shell Script, double click it. Then on text area, replace it with this text:

if [ -n "$*" ]; then
    open -n "$*"
else
    osascript -e 'tell app "Finder" to display dialog "PLZ DRAG AN APP 2 MULTIPLE INSTANCE" with title "MULTIPLE INSTANCE LAUNCHER" buttons { "OH HAI" } '
fi

On Pass input, change it to as arguments. Press command+S, on Save as type: Multiple Instance, on Where, choose Applications, click Save. Quit Automator.

Click Applications, drag Multiple Instance to Dock, preferably near Applications folder.

Click Applications, drag an app(example: Calculator) to Multiple Instance, repeat to launch multiple instance of that app.

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