Google Authentication in Internet Accounts

The thread I was hoping would deliver me from Google frustration is over a year old and Apple suggested I ask a new question. I haven't a question, but perhaps I have an answer. I had to change my Google password last week and that broke something enough that Google would no longer play nicely with my MacBook Pro's High Sierra OS Mail.app. So I deleted accounts, turned my 2-step verification off, cleared out whatever the internet articles and forums suggested, and nothing worked.

I added an app password in my Google account settings: Manage my Google Account, then the clicked the security tab on the left, scrolled to 2-step verification where I'd turned my 2-step verification back on. Then I tapped the disclosure arrow on the right of 2-step verification, I scrolled all the way down, to

App passwords, and entered "Mail" for the App name. I know, brilliant right? Still, Google gave me a "Error 400 invalid_request" when I approached it from the Internet Account panel under System Preferences.

For no good reason except I wasn't willing to give up I tried once more using Mail's Add Account... under Mail on the file menu bar. Selecting Add Account... a panel drops in view with bullet selections, and I

selected Other Mail Account, and what's this? No Error 400 blockage? Nice. I entered my gmail address, and the 16 character app password I set up (without the spaces Google gives you) and dang if it didn't work.

Now let's see how long it works now. It has to break again, right? It can't be that easy.