An excellent avenue of automation. This can now open my daily set of readings in my Profile of choice in specific Multi-Account Containers (of course).
To modify firefoxuser14709930's comment 5 years ago, Windows users can open a page using, say, Profile DAILY and Container WORK in an additional tab in this way:

"C:\Program Files\Mozilla Firefox\firefox.exe" "ext+container:name="WORK"&"url=h...mozilla...org -P DAILY --new-tab
(full urls not allowed here in comments)

25/09/2026

Beautiful. Want to open a bookmark in a container tab? Just use:

ext+container:name=MyContainer&url=https[:]//mozilla[.]org

(eliminate the brackets around the colon & period] Then, search network.protocol-handler.external.ext+container in about:config and double click it to set boolean=true, and you'll eliminate the nag screen!

Thank you Denys H!

I'd love to say this works perfectly, but unfortunately I'm on windows and the protocol handling doesn't seem to work right. Can't blame the dev who is clearly linux based like a sane person.

This addon has become an incredibly useful tool for me to be able to open up containers in a script-able way to allow site access for different purposes. Thank you so much for making this!

Really nice extension!

It's normal to 'disapear' page icon when change path to url in bookmarks into e.g.: ext+container:name=MyContainer&url=https://mozilla.org ??

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Are you planning to add something along the lines of detecting a potential container?
For example, we assign a container to a domain:

*google.com* -> google container

And if, for example, we click on a url call matching the pattern in another program it will open us automatically in a specific container.

Think about this, it would be a brilliant solution!

New Firefox update added a warning each time a tab is opened, someone on github seems to have found a way to make it not appear. https://github.com/honsiorovskyi/open-url-in-container/issues/121#issuecomment-1869443971

Nice extension. A bit annoying since 121.0 in which Firefox added a warning before opening each tab in an custom protocol. Does anyone know how to disable this ?

thank you!!!!!!!!!!!!! this is so helpful...

Excellent, thank you.

Love this extension. No other browser that I know has this capability. One thing I love it for is to be able to have 2 gmail accounts open at the same time in the same browser.

Is working perfectly with the latest version in 2023 ! Had only to figure out how to save bookmarks because it's not really clear. Save it as ext+container:name=MYCONTAINERNAME&url=https://mozilla.org