Well, I don't know the Ubuntu specific part, but in Chrome with KDE you can simply click (probably works with other desktop environments too):<p><pre><code> Menu -> Tools -> Add to desktop
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Et voilà, you have an app with a separate profile in your KDE menu. For example, that is the way I use <a href="https://draw.io" rel="nofollow">https://draw.io</a><p>Didn't know through that it was so easy to get it working with FF too. Thanks :-)
This reminds me of Mozilla prism, which I think is discontinued now. I always liked having a separate window and process for gmail that wouldn't close if my browser crashed