Leaderboard

As far as i know there is no magic flag to enable a ping-pong / forward then reverse loop / patrol cycle style animation. I think the frames are just duplicated in reverse, happy to be corrected though! For apngs my tip to keep file size down would be to minimize the change area between frames (only the rectangle of changed area of each frame is stored in the apng file- see http://littlesvr.ca/apng/inter-frame.html, which probably explains why a ping-pong loop without frame duplication wouldn't work) - and using something like pingo/pinga for compression (https://css-ig.net/)

Did you see the Spinball app reference from this thread?