1319384 - Setting a new animation whose from value does not equal to the base value triggers a new transition

Status: NEW

(Core :: DOM: Animation, defect, P3)

Description

[Hiroyuki Ikezoe (:hiro)]

Attachment: A test case

Attaching test has a 0.3s opacity animation and a 1s background-color transition.

If transition-property is all, the opacity does not get back to the initial value while running the  background-color transition.

If transition-property is background-color, this bug does not appear at all.

Though the opacity value persists after the transition finished, but it will be fixed by bug 1318697.

Note that I see this bug on ESR 45.

Comment 1

[Hiroyuki Ikezoe (:hiro)]

Devtools shows that there is a 1s opacity transition (1.0 -> 0.5)!

Comment 2

[Hiroyuki Ikezoe (:hiro)]

Attachment: Another test case

Setting a new animation whose from value does not equal to the base value triggers a new transition.

Comment 3

[Brian Birtles (:birtles)]

There's already at least one spec bug in this area. See bug 1192592.

Comment 4

[Hiroyuki Ikezoe (:hiro)]

Thanks! Yes, I think this is somewhat related to bug 1192592.  I am reading the spec now.   In this case,  we compute the base value as startValue and compute the from value of the animation as endValue in nsTransitionManager::ConsiderInitiatingTransition().

What I don't still understand is that setting animation's property (changing keyframes too) is a style change event or not.

Comment 5

[Hiroyuki Ikezoe (:hiro)]

IIUC, bug 1192592 is an issue about the before-change style when an CSS animation is removed,  whereas this bug is an issue about the after-change style when an CSS animations is added.