[MattBearman]

I'm in the same situation, and I hope this never gets a fix from Google, as like you I like being able to tell the difference when the tabs are too small to show the email address.

[ozh]

Or use an extension to change the favicon, such as https://chrome.google.com/webstore/detail/i-hate-your-favico... (change favicon on url google.com/mail/u/0/ or /1/ etc..)