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How do I install two different versions of Firefox on the same machine?

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For some years, my home PC was never connected to the Internet. I was happily using Firefox ver. 14 for frequent off-line work. Recently, I started using this PC to go on-line so I upgraded FF to the latest ver, 48, for security reasons when going on-line.

To my dismay, there are two changes from ver. 14 which are big deficiencies for my off-line use. First, ver. 48 has a minimum width of about 300 pixels for the white space (the page display area) in the window, which is too wide for some of my off-line work. Ver. 14 could be made much narrower than this. Second, on the context menu for the control bars at the top of the window, there was an option to hide the navigation bar. This is gone in ver. 48.

I found the plug-in Hide Navigation Bar, but, while an improvement, it is unsatisfactory because there seems no way to always hide the navigation bar, for it keeps popping up when one mouses over the menu bar, quite annoying because the navigation bar is irrelevant to my off-line use.

I looked without success for a plug-in for changing the minimum window width. I also looked at about:config, filtering the Preference Name for "width" and then "size", but saw nothing that seems appropriate.

I'm willing to try a plug-in for the window width issue. There may also be a config Preference I can add that will do the same.

Otherwise, is it possible to install two different versions of Firefox on the same PC? If so, how?

For some years, my home PC was never connected to the Internet. I was happily using Firefox ver. 14 for frequent off-line work. Recently, I started using this PC to go on-line so I upgraded FF to the latest ver, 48, for security reasons when going on-line. To my dismay, there are two changes from ver. 14 which are big deficiencies for my off-line use. First, ver. 48 has a minimum width of about 300 pixels for the white space (the page display area) in the window, which is too wide for some of my off-line work. Ver. 14 could be made much narrower than this. Second, on the context menu for the control bars at the top of the window, there was an option to hide the navigation bar. This is gone in ver. 48. I found the plug-in Hide Navigation Bar, but, while an improvement, it is unsatisfactory because there seems no way to always hide the navigation bar, for it keeps popping up when one mouses over the menu bar, quite annoying because the navigation bar is irrelevant to my off-line use. I looked without success for a plug-in for changing the minimum window width. I also looked at about:config, filtering the Preference Name for "width" and then "size", but saw nothing that seems appropriate. I'm willing to try a plug-in for the window width issue. There may also be a config Preference I can add that will do the same. Otherwise, is it possible to install two different versions of Firefox on the same PC? If so, how?

All Replies (7)

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I would suggest using the Firefox Portable Edition of 14.0.1 and "install it" to your hard drive. It will peacefully co-exist with the latest Release version and will have its own Profile (where user data and customizations are held).

https://sourceforge.net/projects/portableapps/files/Mozilla%20Firefox,%20Portable%20Ed./Mozilla%20Firefox,%20Portable%20Edition%2014.0.1/

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As long as you are not going online there is not much additional risk from using an outdated Firefox. It is possible to install multiple ordinary Releases instead of portable, but as a Windows user the-edmeister's suggestion is probably the best method for you to use.

See also

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Recently, I started using this PC to go on-line so I upgraded FF to the latest ver, 48, for security reasons when going on-line.

The "problem" with using 'ordinary Releases' is that the differences between Firefox 14 and Firefox 48 complicates the situation. You would need separate Profiles for each and need to be very careful that each version of Firefox is opened with the correct Profile every time.

The Portable version creates it own Profile and will only launch with its own Profile; the official Release won't even know that you have a Firefox Portable version installed and won't "see" the Profile for the Portable version.

Plus Firefox Portable is a bit easier to disable application updates with and not be surprised by an update to the latest version "accidentally" as can happen when the user 'thinks' they disabled "updates" - as can happen with the Mozilla Maintenance Service. Portable doesn't contain that "feature". Ya tell Portable to "Never check for updates" and it will never check for and install an update.

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Thanks to both the-edmeister and John99 for their replies.

Unfortunately, I cannot make the portable edition of FF 14.0.1 actually run version 14. I installed it several times on my hard drive (to the folder C:\temp\) and then later on a USB flash drive. In all cases, when I "run" FirefoxPortable.exe, I briefly see a splash screen that announces this is the Portable Edition of Firefox, but what I get is the regular FF ver. 48.

The first time I tried running Portable Firefox 14, I had the installer launch it. I did this before reading the "Testing pre-release versions" article John99 listed. It cautions against letting the installer launch pre-release versions of FF.

Help.

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Why did you install it here? C:\temp\

http://kb.mozillazine.org/Testing_pre-release_versions#Installing_multiple_versions Doesn't apply to the Firefox Portable version. That's why I recommend using the Portable, its a lot simpler to use. Mixing & matching the two different recommendations has got you messed up somehow. https://en.wiktionary.org/wiki/too_many_cooks_spoil_the_broth

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Actually, I installed Firefox Portable in

   C:\temp\program_files\Firefox_ver_14

And the installer created the sub-folder FirefoxPortable. I put it there because the installer refused to continue when I tried putting it in

   C:\Program Files (x86)\tools\Firefox_ver_14

stating that location is "invalid" (had the same problem with Strawberry Perl). I surmise that both installers balked at the spaces in the pathname. FF ver. 48 64-bit is in

   C:\Program Files\tools\Mozilla Firefox

The only mixing and matching I did was that, after the first time of having the installer launch Firefox Portable, I went to the FirefoxPortable folder and double-clicked on the file FirefoxPortable.exe. So even more now I don't understand why it's not working.

I'm wondering if uninstalling ver. 48 (only if I can be certain that won't remove my profile with its settings and history), removing Firefox Portable, then reinstalling FF Portable, then ver. 48 will fix the problem.

robinel. modificouno o

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Uninstalling Firefox 48 won't affect your Profile for Firefox 48, nor will it affect Firefox Portable. Portable isn't "installed", there's no Registry entries - so Windows isn't even aware that it's there, as far as "Programs and Features" is concerned in the Control Panel.

As to why double-clicking on "FirefoxPortable.exe" isn't working, I have no idea. I always right-click that file and use Desktop(create shortcut) to create a desktop shortcut for Portable.