The firefox4-4.0-0.4.beta3 package install this new version besides the version 3.x. So you will have 2 entries in the Internet menu.

WARNING : a backup of your profile (~/.mozilla/firefox directory) seems mandatory.

Start by reading :

As always :

yum --enablerepo=remi install firefox4

No xulrunner update, this RPM provides his bundled Gecko engine.

Actually most of the extensions and themes are not compatible and will be disabled.

I start to test the new features and I expect yours feedbacks.

A first SunSpider JavaScript Benchmark reveal a great performance improvement in 64bits.

Mozilla/5.0 (X11; Linux x86_64; rv:2.0b3) Gecko/20100815 Remi/fc13 Firefox/4.0b3
Total:                  748.4ms +/- 4.4%
Mozilla/5.0 (X11; U; Linux x86_64; fr; rv: Gecko/20100724 Remi/fc13 Firefox/3.6.8
Total:                 2029.2ms +/- 2.3%

For memory:

Mozilla/5.0 (X11; U; Linux x86_64; fr; rv:1.9.2b1) Gecko/20091106 Remi/fc12 Firefox/3.6b1
Total:                 2397.0ms +/- 3.0%
Mozilla/5.0 (X11; U; Linux x86_64; fr; rv: Gecko/20091105 Remi/fc12 Firefox/3.5.5
Total:                 3031.2ms +/- 1.5%

A second JavaScript performance test with V8 Benchmark Suite - version 5 confirm this result:

  • Firefox 3.6.8, score 225
  • Firefox 4.0b3, score 812