How to copy and paste plain-text in macOS
On the far left side of your macOS menu bar sits a little apple symbol, click on it and open ‘System Preferences’.
Select ‘Keyboard’.
Select ‘Shortcuts’ menu.
Select ‘App Shortcuts’ from the left list menu.
Click the ‘+’ button.
For ‘Application:’ input box make sure you have ‘All Applications’ selected.
Next type ‘Paste and Match Style’ into the ‘Menu Title’ input box.
In the ‘Keyboard Shortcut’ input box, pretend that you are about to paste something by first pressing the Command key, then the V key.
You should now only see ⌘-v which is the cloverleaf command sign followed by a -v in this box.
Click add.
Done!
Now you can paste plain-text everywhere using Command-V on your Mac without a plugin