Middle-click paste not working in Ghostty on KDE

I upgraded Ghostty and middle-click paste stopped working. Select some text anywhere, middle-click into the terminal, nothing happens. In Firefox, for example, still works, so it clearly wasn't the primary selection itself being broken.

I hit this on Fedora 44 with KDE Plasma 6 on Wayland, running Ghostty 1.3.1, and here's the root cause.

It's the gtk-enable-primary-paste GSetting. Ghostty 1.3.0 started honouring it in #10328, and on my system that key defaults to false, shipped that way directly by gsettings-desktop-schemas (50.0-1 here). No KDE or distro override involved.

Firefox pastes fine because it implements middle-click paste itself and ignores the GTK setting. Ghostty now reads it and respects it, so it doesn't work.

The fix:

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

It takes effect on the next Ghostty launch, since the setting is read once at startup rather than on every mouse-down.

The reason this is so hard to find from a non-GNOME desktop: the schema is namespaced org.gnome.desktop.interface, which reads as GNOME-only, so you don't think to look there. But GTK reads it on every desktop environment, and KDE's System Settings never exposes the key, so there's no GUI path to discover it.

If you're on KDE, Sway or Hyprland and your middle-click paste vanished after an update, that's your culprit.