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can 54.0 and 57.0.2 run at the same time?

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  • Last reply by FredMcD

auntijoan
auntijoan
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My PC is getting very slow, & I frequently get the message that Mozilla "is not responding." Depending what I'm doing I sometimes get the message that Firefox is already running, as though there are 2 versions. Well, looking at my app files, I have "Mozilla 54.0 10/7/17" and "Mozilla 57.0.2 12/8/17." Do I have 2 competing versions? The icons are slightly different. Was one to replace the other? I did have 2 different icons for Firefox on my desktop screen for a time. Basically, can I safely remove the 54.0 version, if that's what causing the problem? Will I be losing anything? Thanks!

My PC is getting very slow, & I frequently get the message that Mozilla "is not responding." Depending what I'm doing I sometimes get the message that Firefox is already running, as though there are 2 versions. Well, looking at my app files, I have "Mozilla 54.0 10/7/17" and "Mozilla 57.0.2 12/8/17." Do I have 2 competing versions? The icons are slightly different. Was one to replace the other? I did have 2 different icons for Firefox on my desktop screen for a time. Basically, can I safely remove the 54.0 version, if that's what causing the problem? Will I be losing anything? Thanks!

All Replies (1)

FredMcD
FredMcD
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First, when running different versions of the browser, each should have its own profiles folders because of compatibility issues.

Second. Each version must run in its own separate process. Otherwise, you may get the 'already running' message.

Here is an example of how to run a Firefox separately from any others; Note: All on one line.

C:\PROGRA~1\MOZILL~1\firefox.exe -no-remote -new-instance -new-window -P Firefox_v_57 

Firefox Commad Line Options

Usage: C:\PROGRA~1\MOZILL~1\firefox.exe [ options ... ] [URL]
      where options include:

 -h or -help        Print this message.
 -v or -version     Print Firefox version.
 -P <profile>       Start with <profile>.
 -migration         Start with migration wizard.
 -ProfileManager    Start with ProfileManager.
 -no-remote         Do not accept or send remote commands; implies -new-instance.
 -new-instance      Open new instance, not a new window in running instance.
 -UILocale <locale> Start with <locale> resources as UI Locale.
 -safe-mode         Disables extensions and themes for this session.
 -console           Start Firefox with a debugging console.
 -jsconsole         Open the Error console.
 -browser           Open a browser window.
 -new-window  <url> Open <url> in a new window.
 -new-tab     <url> Open <url> in a new tab.
 -preferences       Open Options dialog.
 -search     <term> Search <term> with your default search engine.
 -setDefaultBrowser Set this app as the default browser.