886376 - Reduce interval between swapping in a preloaded newtab page and preloading the next one

Status: RESOLVED FIXED

(Firefox :: Tabbed Browser, defect)

Description

[Tim Taubert [:ttaubert] (inactive)]

Attachment: reduce interval between swapping in a preloaded tab and preloading the next one

Bug 875509 introduced an interval that makes us wait before starting to preload the next newtab page in the background after swapping in a preloaded one. It's currently set to 3s and I think that's way too high.

The interval was introduced to not interfere with the tabopen animation so we should reduce it to something like 500ms as the tabopen animation itself takes about 250ms. If we leave it at 3s there's a good chance we start preloading the next newtab page exactly when a user just clicked a thumbnail.

Comment 1

[Avi Halachmi (:avih)]

Comment on attachment 766749 [details] [diff] [review]
reduce interval between swapping in a preloaded tab and preloading the next one

Review of attachment 766749 [details] [diff] [review]:
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500ms sounds a bit tight - I've observed 350ms animation on slow systems, and it might even take a bit more.

The optimal approach would probably be to start preload some time (200ms?) after tab animation has finished. However, AFAIK there's no event to indicate scroll-end when the tabstrip has overflow (and the new tab doesn't animate but rather scrolls into view).

Since it probably isn't worth the extra code complexity, Tim and I decided that 600ms should be enough for the vast majority of cases (to start after all animations have finished), and quick enough for real-world cases where users manually open a new tab.

r=me after changing to 600ms.

Comment 2

[Tim Taubert [:ttaubert] (inactive)]

https://hg.mozilla.org/integration/fx-team/rev/3cb980ee5440

Comment 3

[Tim Taubert [:ttaubert] (inactive)]

https://hg.mozilla.org/mozilla-central/rev/3cb980ee5440