Your AlertDesk mailbox

AlertDesk reads your newsletters from a Gmail account kept just for them. It only reads: it never deletes, moves, marks as read or sends anything.

Steps

Make a new Gmail account just for AlertDesk — for example yourname.alerts@gmail.com. Not your everyday mail.
Turn on 2-Step Verification for that account: in its Google Account, Security → 2-Step Verification. Adding a phone number is simplest. Don't set it up with passkeys only: Google then doesn't offer app passwords.
Make an app password: signed in to the new account, go to myaccount.google.com/apppasswords, name it AlertDesk and press Create. Google shows 16 letters once — leave that page open.
In AlertDesk: Settings → Mailbox → Connect the mailbox. Type the address and the 16 letters (with or without the spaces) and press Connect. The app password is kept only in your computer's keychain, never in AlertDesk's data folder.
From any mail account, send a short letter to yourname.alerts+test@gmail.com. Then press Check now on the Mailbox page.

The Mailbox page says Connected: yourname.alerts@gmail.com and reads the folder [Gmail]/All Mail.
After Check now: Test letter received — the mailbox works. Health stays green.
From then on AlertDesk checks every 15 minutes while it's running.

"Gmail didn't accept that address and app password": check the address, make a new app password (an old one may have been removed) and type it again.
No "App passwords" page: 2-Step Verification isn't on yet, or the account uses passkeys only. Turn on 2-Step Verification with a phone number, then try the page again.
No test letter: wait a minute and press Check now again; check that the address has +test just before the @.
Health says "Reconnect mailbox": the app password was removed at Google. Make a new one, then Disconnect and Connect again on the Mailbox page.