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How to run two versions simultaneously on a Mac?

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  • Last reply by troels

troels
troels
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I have a heavily customised FF v42 setup I am happy with but my Firefox version is seriously out of date and it's time to upgrade. I suspect a lot of things will no longer work on the latest version (particularly some of my old addons).

To ease the transition I want to be able to run my old version (temporarily for say a few weeks) and the latest one simultaneously so I can customise the new one the same standard and find solutions for anything that is no longer supported and still use my old install/addons until that transition is completed.

I found this thread:

https://support.mozilla.org/en-US/questions/1061740

but the solution pointed to has links that no longer work. I couldn't find anything recent on the web or youtube that covers the Mac.

I understand the principles will be to:

1. Install current version in a different location. Is that just dragging the FF .app file to somewhere other than the Applications folder or is it asked as part of the install?

2. Use a different profile for each install. Not sure the sequence of doing this so that I don't lose my current (old) profile. I'm guessing it's create a new profile, switch to the new profile and then install current version which will "take over" the new profile. Then I can switch back to the old one when I run my my old FF?

Any help greatly appreciated.

I have a heavily customised FF v42 setup I am happy with but my Firefox version is seriously out of date and it's time to upgrade. I suspect a lot of things will no longer work on the latest version (particularly some of my old addons). To ease the transition I want to be able to run my old version (temporarily for say a few weeks) and the latest one simultaneously so I can customise the new one the same standard and find solutions for anything that is no longer supported and still use my old install/addons until that transition is completed. I found this thread: https://support.mozilla.org/en-US/questions/1061740 but the solution pointed to has links that no longer work. I couldn't find anything recent on the web or youtube that covers the Mac. I understand the principles will be to: 1. Install current version in a different location. Is that just dragging the FF .app file to somewhere other than the Applications folder or is it asked as part of the install? 2. Use a different profile for each install. Not sure the sequence of doing this so that I don't lose my current (old) profile. I'm guessing it's create a new profile, switch to the new profile and then install current version which will "take over" the new profile. Then I can switch back to the old one when I run my my old FF? Any help greatly appreciated.

Modified by troels

Chosen solution

Installing multiple versions on Mac OS X is basically dragging the Firefox application out of the DMG file to the desktop and rename the folder. You can drag the renamed Firefox application folder to the Applications folder like you would normally install Firefox.

You need to use the terminal to create a new profile for that version. Make sure that no profile is selected as the default to make the Profile Manager show when you start Firefox. You can check that in the profiles.ini file.

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cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Chosen Solution

Installing multiple versions on Mac OS X is basically dragging the Firefox application out of the DMG file to the desktop and rename the folder. You can drag the renamed Firefox application folder to the Applications folder like you would normally install Firefox.

You need to use the terminal to create a new profile for that version. Make sure that no profile is selected as the default to make the Profile Manager show when you start Firefox. You can check that in the profiles.ini file.

troels
troels Question owner
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Thanks, all good