Apple Mail asks for Google login on a daily basis. This happens to both my personal and work gmail account. I tried generating app specific password but when i go to preferences -> account information: there is no field for a password.
This has been happening only since I have upgraded to 10.12.4.
I couldn't reproduce the issue easily - not until the next prompt for password shows.
Update
I tried deleting and re adding the accounts. It did not fix the issue. Worse, I could not log back into my account this time the google login prompts. It was stuck at a gray screen after entering the password.
However, updating to the latest public beta just now resolved the issue.