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Does anyone know of what file Firefox uses, on a mac, to trigger a startup in safe mode? I am on a mac, and I have not been able to find out what Firefox does to mark that it needs to startup in Safe Mode. There has been methods to bypass safe mode, but I am looking for a way to nip it in the butt before the program launches.


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"nip it in the butt" - Ouch! (I hope no-one edits it out, sounds more, umm, apt somehow :) – Karan Nov 3 '12 at 23:34
Why do you want to know? Is Firefox opening in safe mode without you explicitly setting this? Do you never want Firefox to open in safe mode? – Wk_of_Angmar Nov 4 '12 at 0:32

It uses a command line argument, not a file. I believe this to be true on Firefox compiled for macs too.

$ firefox --help 
Usage: firefox [ options ... ] [URL]
       where options include:

X11 options
  --display=DISPLAY  X display to use
  --sync             Make X calls synchronous
  --g-fatal-warnings Make all warnings fatal

Firefox options
  -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         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.
  -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 Preferences dialog.
  -search     <term> Search <term> with your default search engine.
  -private           Enable private browsing mode.
  -private-toggle    Toggle private browsing mode.
  -setDefaultBrowser Set this app as the default browser.
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