how do I run separate profiles?

With Firefox, I'm used to running this command to open a separate browser with a separate profile:

firefox --no-remote -P "for-github"

When I try the same with Torbrowser, I get an error message:

./start-tor-browser --no-remote -P "for-github"

it pops up a dialog box saying "Tor Browser is already running, but is not responding. To open a new window, you must first close the existing Tor Browser process, or restart your system."

How do I run separate profiles simultaneously?

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Username: zooko3