What happens when you try this (all one line):

"C:\Program Files\Mozilla Firefox\firefox.exe" -private-window https://www.userchrome.org/

I would expect a new private window to open to that URL. What do you get?

• Error message
• New window, but page is blank (or it's your home page)
• New window with the expected page but it's not a private window
• Something else

By the way, I usually paste into the search box on the Windows 10 Taskbar and press the Enter key to execute the command line. You also could use the Run dialog (Windows key + R to open).

jscher2000 said

What happens when you try this (all one line): "C:\Program Files\Mozilla Firefox\firefox.exe" -private-window https://www.userchrome.org/ I would expect a new private window to open to that URL. What do you get?

• Error message
• New window, but page is blank (or it's your home page)
• New window with the expected page but it's not a private window
• Something else

When I paste that command in and press enter, it opens a new tab and goes to that URL but I dont think its a private window. The address appears in history so that makes me think its not a private window. I'm running all this from the command line.

Yes, a new tab in an existing window definitely would not be a new private window.

What do you mean by "the command line"?

jscher2000 said

Yes, a new tab in an existing window definitely would not be a new private window. What do you mean by "the command line"?

command line meaning command prompt.

Hmm, it should still work in cmd.exe.

What if you try this:

"C:\Program Files\Mozilla Firefox\firefox.exe" -private-window "about:privatebrowsing"

Do you get a page warning that it's not a private window?

Can you launch private windows from inside Firefox?

jscher2000 said

Hmm, it should still work in cmd.exe. What if you try this: "C:\Program Files\Mozilla Firefox\firefox.exe" -private-window "about:privatebrowsing" Do you get a page warning that it's not a private window? Can you launch private windows from inside Firefox?

yeah, it opens a new tab and says "you are currently not in a private window." plus a button that says "open a private window". yeah, I can open private windows by using the keyboard shortcut or going through the menu.

What makes you think that this is not a Private Browsing mode window?

cor-el said

What makes you think that this is not a Private Browsing mode window?

websites show up in the history? I don't know how to tell if the window that opens is private other than if it leaves a history. unless thats wrong.

I can't explain why the command-line switch isn't working normally on your Firefox.

What about a regular new window, is it also converted to a new tab?

"C:\Program Files\Mozilla Firefox\firefox.exe" -new-window https://www.userchrome.org/

If so, is it possible you have any extensions that intercept new windows and convert them to new tabs instead?

jscher2000 said

I can't explain why the command-line switch isn't working normally on your Firefox. What about a regular new window, is it also converted to a new tab? "C:\Program Files\Mozilla Firefox\firefox.exe" -new-window https://www.userchrome.org/ If so, is it possible you have any extensions that intercept new windows and convert them to new tabs instead?

When I enter that command, it opens a new window. I don't have any extensions that should affect the opening of tabs or windows.