> Just curious, is there data about how often this happens? Does it affect > to key event listeners added to the document only, or do we disable this > also for other event listeners in any element?
I'm not aware of any data on this. From my testing, it can be quite common. We disable this when there are keydown, keypress, keyup listeners that would be triggered by a key event. So when nothing is focused we check for listeners on the document. If the focus is on an element, we check for key listeners up to and on the element. > Also, I assume this affects only to keypress events? Or also to other > kind of key events? This affects the other kinds of key events too. For keyboard APZ we need to track the focus/selection of a page in order to know what frame to scroll. This can change at any moment from JS. Either in response to user input with event listeners, or at any other moment in setTimeout or rAF. We made the decision to be conservative and respect synchronous changes in response to user input, but not from setTimeout and rAF. So to do this we need to use the synchronous code path when there are key event listeners. > Also, is bug 1352654 the right tracking bug? Doesn't seem related at a > glance. Whoops, the correct tracking bug is bug 1376525. Copied the wrong one. ________________________________________ From: dev-platform <dev-platform-bounces+rhunt=eqrion....@lists.mozilla.org> on behalf of Emilio Cobos Álvarez <emi...@crisal.io> Sent: Saturday, July 22, 2017 12:43:31 PM To: Ryan Hunt; dev-platform@lists.mozilla.org Subject: Re: Keyboard APZ has landed on Inbound On 07/22/2017 08:05 AM, Ryan Hunt wrote: > Keyboard APZ can't be used in every case. Currently it's disabled in the > presense of key event listeners, as they can preventDefault scrolling and that > is a non-negotiable part of the web. Just curious, is there data about how often this happens? Does it affect to key event listeners added to the document only, or do we disable this also for other event listeners in any element? Also, I assume this affects only to keypress events? Or also to other kind of key events? I would expect quite a few pages to use them... > There may be issues with this enabled. Please test this out, and if you find > any regressions please file bugs blocking bug 1352654. Also, is bug 1352654 the right tracking bug? Doesn't seem related at a glance. -- Emilio _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
