 In December 1940, the Board of Supervisors added to the "new" flag the name "San Francisco" in bold, blue letters and codified all of these elements as the official San Francisco flag.The yellow border, now reproduced as a part of the flag, was originally intended to be a gold fringe, but mistakenly became incorporated into the design.When used indoors, as is the custom, a gold fringe is added to what was originally intended to be the fringe.