What are the current requirements and procedures for COVID-related visa extensions in Thailand?

>Is the visa immigration office open as usual? Concerned about COVID restrictions and if the operating hours have been affected in anyway.

Yes, it's open as normal.

>I would like to apply for the 60-day extension under the "COVID-unable to travel" option. Anything I need to provide to get approved for this?

Different immigration offices have different requirements, but all require the following:

1. Your passport and:

a. a copy of your data ("picture") page

b. a copy of your most recent visa (if you have one)

c. a copy of your most recent stamp

d. a copy of your departure card

2. A TM30, filed in the immigration office.

3. The forms (each immigration office may have different forms)

4. A letter from your embassy saying you can not return, OR a print out from your embassy saying they don’t issue the letters.

5. 2x passport pictures

6. 1,900 THB.

Different immigration offices have different policies. *SOME* may require:

- The ID card of the property owner where you are staying

- Copies of *ALL* stamped pages in your passport

>Any advice to make my day trip to the government office easier and go smoothly?

Depends on the immigration office. some have applications to make an appointment, and some don't.