v1.5.1 — triple-click for the ruler

The page-gesture that toggles the reading ruler is now a triple-click instead of a double-click, so it's much harder to trigger by accident. Still an option (on by default), still ignored on links / buttons / form fields. The keyboard shortcut (Alt+R) and the popup toggle are unchanged.

Full changelog: v1.5.0...v1.5.1