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Can't open new tabs in Firefox from the command line on a Mac

  • 2 replies
  • 1 has this problem
  • 9 views
  • Last reply by cor-el

bronco_popsicle
bronco_popsicle
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If I run 

   /Applications/Firefox.app/Contents/MacOS/firefox -new-tab https://www.mozilla.org

when Firefox is already running, I get the error "A copy of Firefox is already open. Only one copy of Firefox can be open at a time." It is true that Firefox is already running, but what I am shooting for is getting a new tab in the already running instance, as the -new-tab flag indicates. I get this problem even if the already running instance was started with exactly the same command.

Some of the flags at https://developer.mozilla.org/en-US/docs/Mozilla/Command_Line_Options explicitly say they open new tabs or windows within an existing instance of Firefox, such as -private-window, but I get the same behavior with those flags. What am I doing wrong?

If I run /Applications/Firefox.app/Contents/MacOS/firefox -new-tab https://www.mozilla.org when Firefox is already running, I get the error "A copy of Firefox is already open. Only one copy of Firefox can be open at a time." It is true that Firefox is already running, but what I am shooting for is getting a new tab in the already running instance, as the -new-tab flag indicates. I get this problem even if the already running instance was started with exactly the same command. Some of the flags at https://developer.mozilla.org/en-US/docs/Mozilla/Command_Line_Options explicitly say they open new tabs or windows within an existing instance of Firefox, such as -private-window, but I get the same behavior with those flags. What am I doing wrong?

All Replies (2)

bronco_popsicle
bronco_popsicle Question owner
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It appears that as of five years ago this was a known bug with no intended fix: https://bugzilla.mozilla.org/show_bug.cgi?id=393645

cor-el
cor-el
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Try: