v2.4.0

• Fix sync for edited styles.
• Fix #2143 from previous releases.
• Right-click or long-press on checkbox in popup to toggle in current tab.
• Use icons instead of some text labels at the top in compact editor layout.
• Speed up live preview a bit with @preprocessor by extracting sections on the fly.
• Use instant inject mode in same-origin iframes too.
• less 4.6.6, csslint-mod 1.0.13.

Full Changelog: v2.3.35...v2.4.0