What new requirements should I expect for a Non-O 'Thai Wife' visa extension in Bangkok?

Hello amazing people of Thai Visa Advice!

A quick update with some possibly relevant information for people with Non-O "Thai Wife" visas in Bangkok, and a short question following a visit to Chaeng Watthana Immigration office yesterday to apply for my first 1 year extension on a Non-O "Thai Wife" visa. Everything went rather smoothly this time (1 hour total time spent at the Bureau of Immigration).

One new thing for us: The immigration officer requested that we make an extra B&W copy of some of the documents we had brought with us (namely the 6 couple pictures, her 2 Tabian Baan and all land documents/Chanote), 1st page of my passport, and her ID Card.

The officer also had my wife fill a form we had never seen before, and which is not in the required document list, and we also had to make an extra B&W photocopy of it. I asked my wife to take notes about the document so we could download it online and fill it (and copying it) before going back there next year. My goal is to streamline the process to perfection and not being sent down to the copy shop again.

The form was about her attesting to our relationship with general information. The document is called หมายเลข 3 กก.2 บก ตม.1 But I wasn't able to find it online. I was wondering if an expert among you would be able to provide more info or to tell me where I can download it? Once we have this, we should be able to make it in and ouf of immigration within 15 minutes next time, without being sent out to make copies and bring some new documents again.

Thanks in advance, as usual, and hopefully, someone finds this information useful!