Possibly you could create a global variable that stores a value and check against this on layout load.
localStorage.fired = true; /// create this after the animation. (i.e at the end of the timeline)
then on layout load create the check
if (!localStorage.fired) {
hypeDocument.continueTimelineNamed('Main Timeline', hypeDocument.kDirectionForward) /// of course this will be whatever you've named you timeline
} else {
// do something on layout load if the animation has already played
}
NOTE You have to also pause the timeline if you are using the Main timeline / another one on layout load. We are using localStorage because we don’t want the variable to disappear after we change layouts. Also if you need to fire the timeline when user closes window and comes back you need to get rid of the localStorage variable (or store as a cookie with an expiry)
at least this is what I would do