Is it true if im applying for new passport and my visa ends December 30th I cant extend on the temp one they give me until my new one arrives?

Hi. Got my new Non-O multiple entry visa a couple of months ago, good for one year, from Ho Chi Minh but that passport is now full. Have applied for a new one and should have it next week. Do I need to get to Immigration and transfer the visa into my new passport or do I have to carry my old and new passports together when entering and exiting the Kingdom? Thanks.

I'm thinking of taking my thai family to Myanmar via mae sot for a day was wondering do they need a passport or just there I'd cards i know Laos they just needed there I'd cards

Got a friend here from Finland on a 30-day exempt entry (with 30 day extension) who is going to do a visa run to Vientiane. His passport is expiring in under 6 months, so he acquired a new one in Bangkok and got it today.

Does he need to get the stamp transferred to the new passport at Chaengwattana before exiting? Or would he be able to exit with both passports (stamp in old one) and apply for a Lao visa + new TRV with the new one?