Shrug is a small program where you can have a library of named strings. You can then search for those strings to have them readily available in your clipboard.
This is what it looks like:
I suggest you add a key binding in your window manager to launch shrug.
Note that shrug keeps running in the background after being launched. This is because in X.org, the clipboard content belongs to the program the content originated from. If the program terminates the content of the clipboard gets cleared. (An alternative would be to use a clipboard manager ¯\_(ツ)_/¯.)