firefox 4.0 beta 6 (how to use it along firefox 3)

The firefox 4.0 beta is in the 6th release. This is the first ff4 release that I have tested.

Firefox uses only one process for all windows, so you can not open two different firefox at the same time. Well, you can but not with the same profile. So in order to use ff4 without losing my ff3 plugins and usability I need to create first a new profile and then a symlink to launch ff4.

1.  first of all install ff4 with another name

• I tried to raname ff4 in the dmg installer but was not possible, so used the terminal in my mac
• cp -r firefox.app /Volumes/Macintosh\ HD/Applications/Firefox-4.0.app

2.  Create a new profile

• In my macOS (change your path for  linux or windows), open the terminal and type:
• /Volumes/Macintosh\ HD/Applications/Firefox-4.0.app/Contents/MacOS/firefox-bin -profilemanager -no-remote
• Then add a new profile "ff4"

3. Create an alias in your .bashrc
• alias ff4='/Volumes/Macintosh\ HD/Applications/Firefox-4.0.app/Contents/MacOS/firefox-bin -P ff4 -no-remote'
• -no-remote tells firefox not to use the running instance but create a new one. You can use only one profile at a time though.

Note: you can copy your data from the older profile to the new one if you wish, or create a backup:

• rsync -av ~/Library/Application\ Support/Firefox/Profiles/n6jajvmu.default  ~/personal/firefox_backup