Mozilla has updated its packaging format for Firefox on Linux, moving from .tar.bz2 to .tar.xz. The switch, which uses the LZMA compression algorithm, results in smaller download sizes — up to 25 percent smaller — and faster decompression times, improving installation efficiency.
The .tar.xz format is widely supported across modern Linux distributions, ensuring compatibility while saving bandwidth. Current users won’t need to take any action, as Firefox will continue updating as usual. However, the new format is now available for Firefox Nightly and will roll out to Beta and Release channels in the coming weeks.
Mozilla chose .tar.xz over Zstandard (.zst) due to its superior compression capabilities, despite slightly slower decompression speeds. Package maintainers and script users are encouraged to update their workflows to handle the new format.