[basilisks]

This sounds terribly convoluted compared to turning on mouse mode and selecting the text with your mouse. It should copy immediately after you release the button, and you should be able to paste with your standard shortcut if you set up tmux to use the clipboard of your choice.

[simias]

Mouse-driven flows are always a little more intuitive and discoverable, but keyboard shortcuts are more precise and can be lightning fast once you have muscle memory.

Listed the way the parent does it seems very complicated, but if you have the sequence memorized and trained it can be executed very quickly and without moving your hands from the keyboard.