Thank you! This allowed me to use Bard without going into Incognito mode!

Works great for bookmarks. </sarcasm>

For bookmarks use https://bard.google.com/?authuser=whatever@gmail.com

while we're here showing people the account-hopping techniques for Google's painful world of auth'ing: the `?authuser=` trick can also be used with numbers from 0-9, to authenticate (by zero-index) your web browser's 10 slots for logged-in accounts (e.g., `?authuser=2` to authenticate your third account slot).

TIL