Firefox 153 adds containers, HDR video on Windows, PDF merging, and JPEG XL image support

Mozilla has released Firefox 153, delivering a range of updates for desktop and mobile users. With this version, Windows users gain High Dynamic Range (HDR) video playback, provided their display supports HDR mode, not just HDR video streaming. PDF handling receives a major enhancement, as users can now merge multiple PDFs by dragging files into the PDF sidebar and add images as new pages using the built-in editor.

This update also previews containers, a feature that allows users to keep separate parts of their online lives in distinct browser tabs for work, shopping, personal, banking… Each container isolates cookies and ad tracking, integrating the functionality of the Multi-Account Containers extension directly into Firefox.

Following these core changes, users can share any web page via a QR code, pick and copy colors directly from the address bar using a quick action, and notice the location permission icon highlighted in red whenever a site gains access. The release also adds support for Apple's system-wide full-screen keyboard command and now verifies Qualified Website Authentication Certificates (QWACs) to support eIDAS regulations.

Additional enhancements include improved video overlay action access, experimental JPEG XL image format support, and Smart Window upgrades with selectable AI models. For mobile users, this release brings organized tab groups on Android, and Quick Answers that enable voice queries with concise responses on iOS.