I'm gonna say it again. I just wanna be able to paste an image that's copied to my clipboard.

I use CleanShot, but you can copy/paste native OSX screenshots by holding down the control key: support.apple.com/guide/mac-help… (Scroll to “Take pictures using keyboard shortcuts“)

Holding down the control key does copy it to the clipboard (Great tip, didn't know that one) but Posts still doesn't let me paste it here in the app like I can in every other social app.