Do I need to show the source of 400k as originating from overseas for a marriage extension in Thailand?

The discussion confirms that while the 400,000 baht for a marriage visa extension does not need to be sourced from overseas, it must be held in a Thai bank account in the applicant's name for at least two months prior to the application date. It is also required to show proof of a monthly income of 40,000 baht, which can come from an international bank account or pension, without needing recent statements.