Mozilla has released Firefox 139.0, introducing several useful improvements aimed at enhancing usability and workflow organization.

Key Changes:

• Added translation support for Firefox extension pages using the moz-extension:// URL scheme.
  
• Implemented custom image and color backgrounds for new tab pages. This feature may roll out gradually. To enable it immediately, activate via Firefox Labs.
  
• Added new background images, including a "Celestial" category.
• Introduced experimental Link Previews feature (enable via Firefox Labs). Use Alt + Shift while hovering links to preview pages.
  
• PNG images now preserve transparency when pasted into Firefox.
• Significantly improved HTTP/3 data transfer performance, particularly noticeable on resumed connections (QUIC 0-RTT) and high-bandwidth/high-latency connections.

Existing Firefox users can update through the browser's settings. Alternatively, download Firefox 139 directly from Mozilla's official site.

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