Adds colored borders to Gelbooru.com gallery search pages to show any images you have already viewed. Also shows which images are animated.
Default colors: very light blue for unvisited, green for visited, yellow for unvisited animated gif or png, purple for visited animated gif or animated png, a less painful to look at shade of blue from the default for unvisited WebM, and red for visited WebM. You can customize these by using the settings link on the right side of the header. Animated png/gif highlighting will only work if the image has been tagged correctly, since unlike with webm there is no real way to tell them apart otherwise.
Important Note: Clearing your browser data will clear the visited history, because this script stores all data locally within your browser. It never stores any data elsewhere itself. You can make backups of your data or transfer it between browsers and devices by using the "Visited History Backups" item on the right side of the header.
This will not work on other Boorus, because the implementation is specifically tied to things that are unique to Gelbooru.