I can't tell you how many times I've accidentally pasted random private stuff from that goddamn middle click into WEB PAGES! Things that can read whatever text you type without having to explicitly submit anything. It's a horrible thing for a new user to discover by accident. It's such an unexpected feature to new users, and no one gets told about it, ever. You simply discover it by accident.

This is a good change, not having it on by default.

To all the haters of this idea, god forbid we make Linux less weird by default for people migrating from Windows.

All that said, I have learned to love select-to-copy and middle-click paste. Especially in the terminal.