From WikiTemp, the GBAtemp wiki
#Leave this line exactly as it is
#Put regular expression fragments (just the part that goes between the //) below
#These will be matched with the URLs of external (hotlinked) images
#Those that match will be displayed as images, otherwise only a link to the image will be shown
#Lines beginning with # are treated as comments
#This is case-insensitive
^https?://gbatemp\.net/
^http://wiki\.gbatemp\.net/

#Put all regex fragments above this line. Leave this line exactly as it is