Then do not? I use a separate browser for each service. I even block the rest of the internet except that service alone,
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You can use the same browser using a portable version. Optionally you can also use an app for each, not webapp, that is just a browser's tab.
Chromium based browser have a similar feature like a container, but it is called an isolation. It works automatically, so you do not have to do anything once enabled.
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