Every email I’ve sent for the last forever has been done with Command + shift + D. It’s a small thing but man it is convenient once you memorise some stuff like that.
Screen shots , Command + shift + 3 for the whole screen. Command + shift + 4 is for screen shotting an individual window or drawing a box around any area of the screen , press the space bar to cycle through them.
So many of the shortcuts I use I don’t even know what I’m pressing because it’s just become muscle memory at this point.