Is a letter from the US Embassy needed to transfer my Non-O visa stamp to a new passport in Thailand?

The conversation discusses the process of transferring a Non-O visa stamp to a new passport after obtaining a new passport. The general consensus among commenters is that a letter from the US Embassy requesting cooperation is no longer needed, as most immigration offices are aware of this policy change. Users mention they successfully transferred their visa stamps by bringing both old and new passports along with any supporting documents, such as a receipt for the new passport. Additionally, some suggested bringing a specific letter from the US Embassy confirming that such letters are not issued anymore as a precaution. Lastly, it is highlighted that the transfer must be done at the immigration office that issued the original visa.