This is an archived snapshot of W3C's public bugzilla bug tracker, decommissioned in April 2019. Please see the home page for more details.

Bug 29519 - Consider specifying MouseEvent#toElement, fromElement
Summary: Consider specifying MouseEvent#toElement, fromElement
Status: NEW
Alias: None
Product: CSS
Classification: Unclassified
Component: CSSOM View (show other bugs)
Version: unspecified
Hardware: PC All
: P2 normal
Target Milestone: ---
Assignee: Simon Pieters
QA Contact: public-css-bugzilla
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2016-03-07 14:50 UTC by Simon Pieters
Modified: 2017-01-10 20:00 UTC (History)
3 users (show)

See Also:


Attachments

Description Simon Pieters 2016-03-07 14:50:52 UTC
https://drafts.csswg.org/cssom-view/

https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit/Source/core/events/MouseEvent.cpp&l=225

// MSIE extension - "the object toward which the user is moving the mouse pointer"

// MSIE extension - "object from which activation or the mouse pointer is exiting during the event" (huh?)

Supported in WebKit and Chromium. Not supported in Gecko.

http://software.hixie.ch/utilities/js/live-dom-viewer/saved/3966

https://github.com/search?p=1&q=%22event+fromelement%22&ref=searchresults&type=Code&utf8=%E2%9C%93 shows some usage.
Comment 1 Simon Pieters 2016-03-07 14:59:37 UTC
The only Mozilla bugs I can find mentioning fromElement or toElement are 
https://bugzilla.mozilla.org/show_bug.cgi?id=961708
https://bugzilla.mozilla.org/show_bug.cgi?id=1205244

Mike, is this something you think Gecko should implement?
Comment 2 Mike Taylor 2016-03-08 02:40:54 UTC
[1] is the only site known to me that has been broken due to lack of support, and luckily an ex-employee got it fixed really quickly. It doesn't seem to be a huge issue for us -- but if we found more proof that it breaks content doing the same thing Blink and WebKit do seems easy.

IIRC when looking at [1], Edge still supports this.

[1] <https://bugzilla.mozilla.org/show_bug.cgi?id=1205244>

(I'm so confused by that other report you listed, I'm not sure what they're asking for).
Comment 3 Mike Taylor 2016-07-29 22:45:36 UTC
Another site depending on this: https://github.com/webcompat/web-bugs/issues/2929#issuecomment-236309173
Comment 4 Chris Rebert 2016-08-28 04:39:08 UTC
Conveniently, Chrome has usage metrics for these 2 properties:
* https://www.chromestatus.com/metrics/feature/timeline/popularity/506
* https://www.chromestatus.com/metrics/feature/timeline/popularity/507
Comment 5 Chris Rebert 2017-01-10 20:00:59 UTC
Draft of tests for .toElement & .fromElement:
https://github.com/w3c/web-platform-tests/pull/4408