Unable to validate: Connection Error

[themightyoarfish]

Prerequisites

• [X] I have searched open and closed issues for duplicates.

Describe the bug

As of recently, I cannot add my gmail account anymore. It worked initially, then around 2 weeks ago kept prompting for the (saved) password. Today it wouldn't accept the generated app password. I removed the account and now adding it fails with

Basically the same as https://github.com/elementary/mail/issues/220, but the workaround there doesn't seem to exist, plus I'm using 2FA with app passwords.

To Reproduce

Steps to reproduce the behavior:

1. Open Google Account > Security and generate app password
2. Open Pantheon mail
3. Click gear icon > Accounts
4. Add gmail account with app password
5. Observe failure

Prerequisites

• [ ] I have searched open and closed issues for duplicates.

Platform Information

Please check what applies: -->

• [ ] I'm using the latest version from git that I've manually compiled
• [X] I'm using the latest released stable version

[OmarShawky1]

this error occurs for yahoo also, before updating.... it was working, but i have 3 emails in pantheon and only the yahoo mail showed this issue, tried to remove the email and re add it, but the same issue