Yes. Two Firefox container tabs can open the same website while keeping separate site sessions. This lets one tab remain signed in as one account and another tab use a different account, provided the website supports both accounts.
How the two sessions differ
Firefox containers keep relevant site data separate between containers, so cookies and other session information in one container are not used as the session in another. Open the same address in each tab, then compare two visible clues: the container label and the account name shown by the website. The connection and device characteristics, including the IP address, do not change merely because the container changes. See Mozilla’s explanation of Firefox containers for the supported behaviour; wording and availability can vary by Firefox version.
Hypothetical reading-account example
Example: A fictional library website is open in two tabs. The first tab has the Work container label and displays the account name reader-work. The second has the Personal label and displays reader-home. Although both address bars show the same library address, the account names confirm that the tabs are using different signed-in sessions. Returning to the Work tab still shows reader-work, while returning to Personal still shows reader-home.
What a blank container does—and does not—show
Opening a new container may show a sign-in page because that container has no existing session for the website. That is not proof that either account was deleted, disabled or signed out everywhere. Check the other container and, if needed, sign in through the website’s normal account process. A container separates browser site data; it does not create an account, merge accounts or grant access to an account without its credentials.
If both tabs show the same account, the intended two-account arrangement has not been demonstrated. Check which account was actually selected in each container instead of treating different tab colours as proof. Containers do not provide anonymity or bypass website permissions.
Responsible entertainment note: This article is for screen reading and risk awareness only. It does not provide betting advice, account service, payment handling, outcome prediction or any guaranteed result.