Mozilla has officially made available distribution packages for Firefox 151, the latest monthly update to its open-source browser. This version was originally rumored to include a native JPEG-XL image decoder, but this feature has been postponed to Firefox 152 beta. This release also brings updates to built-in VPN support, private browsing improvements, several settings tweaks, and the ability to merge multiple PDFs directly in the Firefox PDF viewer.
Among the changes for Linux and macOS, Firefox 151 adds a local configuration file backup function and supports cross-platform recovery. For users who frequently migrate or retrieve Firefox configurations between macOS and Linux, this means that they no longer need to manually copy hidden directories, making transfer and restoration more convenient.
Firefox 151 also adds support for the Document Picture-in-Picture API. This API allows you to create a window that is always on top and put any HTML content into it. It is suitable for custom control panels or supplementary information display in scenarios such as video conferencing, making it more flexible than traditional video picture-in-picture.
Mozilla's developer documentation has been updateddocumentPictureInPictureTo explain, Google Chrome has supported this capability as early as Chrome 116. Official release binaries for Firefox 151.0 are now available for download from Mozilla’s releases page:
https://ftp.mozilla.org/pub/firefox/releases/151.0/