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The seventh beta release in the new Firefox 24.x branch has been made available for download by Mozilla, for all available platforms, including Linux.The binaries for Mozilla Firefox 24 Beta 4 can be downloaded and run without having to install anything. This is true for all the available platforms.
The previous version of Firefox, 23, had gone through ten beta versions before a stable release has been made available. This being said, the seventh Beta doesn't have any specific changes, but you can be sure that Mozilla hasn't been idle.
Download Mozilla Firefox 24 Beta 7 for Windows
Download Mozilla Firefox 24 Beta 7 for Linux
Download Mozilla Firefox 24 Beta 7 for Mac OS X
Remember that this is a development version and it should NOT be installed on production machines. It is intended for testing purposes only.