It's rumored that Thai immigration can access your FB...

The reason these extensions are automatic is so that you don't have to go outside and visit immigration. Stay at home.

Theoretically, you can extend that visa one time for 2 months, so you could turn that 15 months into 17...

What documents are required to file for this 60-day extension of stay based on visiting family? Do we have to show the same docs as the original visa application? I must do this same thing in two weeks.

This is the smart move, but I doubt they'll figure that out.

If you're an asymptomatic carrier, it can stop you from spreading the virus unknowingly. It also stops you from touching your face so much.

Getting a multiple-entry tourist visa is a simple matter of filling out an application at the Thai Consulate or Embassy in his home country, then paying the fee. Even a single entry tourist visa is quite straightforward...I don't know the raw numbers, but very few applicants are rejected for Thai tourist visas. There is no reason for him to show an invitation letter. Coming on a tourist visa to Thailand is much easier for a UK citizen than for a Thai citizen going to the UK.

There is no benefit to mentioning the marriage. As far as Thailand is concerned, he is a tourist. If you are a Thai national, he will be eligible for a non-immigrant O visa based on marriage after you have married, but that's something you can do later. Perhaps others will chime in with something I'm missing, but I don't think you need to mention the marriage.

Well, that sucks. Maybe others can advise on better strategies for your extension in Chiang Mai, but at least it's over for now. :)

In Bangkok, I don't even bother going in the morning. I arrive at 1pm, just after lunch, and wait a few hours in the afternoon. Sometimes it's 2-3-4 hours, sometimes it's just 45 minutes. Why waste the morning?