In Vietnam, Buddha’s birthday is called in Vietnamese, “Lễ Phật Đản/ Phật Đản (佛誕, “Birthday of the Buddha”), or “Ngày Hội Hoa Phật” (Buddha’s Lord Flower Festival Day)” and is celebrated throughout Vietnam. Many Buddhist temples hold celebrations that attract people from around the country, while pagodas around the country are decorated.[35] From 1958 to 1975, the birthday of Buddha (on the 8th day of the 4th month in the Lunar calendar) was recognized as a national public holiday in South Vietnam,[36] enjoyed with floats and lantern parades on the streets. Currently Buddha’s Birthday is still a popular celebrated festival in Vietnam, but not a public holiday.

Source: https://en.wikipedia.org/wiki/Buddha%27s_Birthday

See photos from previous year’s event:  https://photos.app.goo.gl/vSBXtGgoZGAVjFrm8