Disable primary-paste by default

This is an X11ism, originally an xsetting 1 which frequently results is in unexpected behavior when people pressing the middle mouse button.

It's commonly used for other actions or more often getting clicked by accident, and dumping your entire clipboard while having no indication that this will happen is nothing short of a dumpster fire.

People that know about this functionality and really love this functionality can easily override the setting.

gsettings set org.gnome.desktop.interface gtk-enable-primary-paste true

Goodbye X11.

[1.b] 4af29068