You might like Tamper monkey. You can add a button to kick it off or whatever your heart desires.
Tampermoney also works around CORs issues with relative ease.
Userscripts for the win. Consider Violentmonkey over Tampermonkey though.
I love Tamper monkey! I've never made my own scripts though - just used other peoples'.
Userscripts for the win. Consider Violentmonkey over Tampermonkey though.