973604 - Standardize or hide from content Element.prototype.setCapture and Document.prototype.releaseCapture

Status: ASSIGNED

(Core :: DOM: Events, defect, P5)

Comment 1

[David Bruant]

It looks like these are in IE and Gecko, but nowhere else.
Maybe it's time to let them go.

Comment 2

[Markus Stange [:mstange]]

Bug 503943 (where this was implemented) points to http://lists.w3.org/Archives/Public/public-webapps/2008OctDec/0308.html where standardization was attempted. I haven't read up on what happened to that.

Comment 3

[Boris Zbarsky [:bzbarsky]]

I would guess that the standardized version is https://dvcs.w3.org/hg/pointerlock/raw-file/default/index.html or something?

Jonas, is that the case?

Comment 4

[Boris Zbarsky [:bzbarsky]]

And of course the second question is whether this is being used.  Note http://stackoverflow.com/questions/7481022/mouse-capture-in-non-ie-browser and http://news.qooxdoo.org/mouse-capturing and the like...

Comment 5

[Olli Pettay [:smaug][[e-mail]]]

Pointerlock is different feature.
https://dvcs.w3.org/hg/pointerevents/raw-file/tip/pointerEvents.html#widl-Element-setPointerCapture-void-long-pointerId
is close to setCapture.

Comment 6

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

I don't know anything about these functions.

Are these the old netscape versions capturing event listeners (as in, bubbling event listeners vs. capturing event listeners). If so, didn't we remove support for those ages ago?

If these are for pointer lock, I don't know what the latest spec is.

Either way, Olli is probably your guy here.

Comment 7

[Olli Pettay [:smaug][[e-mail]]]

SetCapture is the thing which makes event targeting to use the same target all the time. So, not Netscapeism but IEism.

Comment 8

[Anne (:annevk)]

It seems per comment 2 standardization was attempted and failed? And now there's a new standard Blink/WebKit are interested in implementing? Not sure what the best way forward here would be. Add use counters?

Comment 9

[Olli Pettay [:smaug][[e-mail]]]

I think we should wait for setPointerCapture to be implemented and stable, and then
start warning about use of setCapture/releaseCapture.

Comment 10

[Kagami Rosylight [:saschanaz] (they/them)]

Attachment: Bug 973604 - Add use counters for set/releaseCapture r=mbrodesser

Comment 11

[Kagami Rosylight [:saschanaz] (they/them)]

Attachment: data review request

Comment 12

[Chris H-C :chutten]

Comment on attachment 9180817 [details]
data review request

DATA COLLECTION REVIEW RESPONSE:

Is there or will there be documentation that describes the schema for the ultimate data set available publicly, complete and accurate?

Yes.

Is there a control mechanism that allows the user to turn the data collection on and off?

Yes. This collection is Telemetry so can be controlled through Firefox's Preferences.

If the request is for permanent data collection, is there someone who will monitor the data over time?

Yes, Kagami Rosylight is responsible.

Using the category system of data types on the Mozilla wiki, what collection type of data do the requested measurements fall under?

Category 1, Technical.

Is the data collection request for default-on or default-off?

Default on for all channels.

Does the instrumentation include the addition of any new identifiers?

No.

Is the data collection covered by the existing Firefox privacy notice?

Yes.

Does there need to be a check-in in the future to determine whether to renew the data?

No. This collection is permanent.

---

Result: datareview+

Comment 13

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/1fce98c10f98
Add use counters for set/releaseCapture r=emilio

Comment 14

[Andreea Pavel [:apavel]]

https://hg.mozilla.org/mozilla-central/rev/1fce98c10f98

Comment 15

[Kagami Rosylight [:saschanaz] (they/them)]

Telemetry says 0.04% of pages use setCapture, which is higher than I expected.

https://telemetry.mozilla.org/new-pipeline/dist.html#!cumulative=0&end_date=2020-10-25&include_spill=0&keys=__none__!__none__!__none__&max_channel_version=nightly%252F84&measure=USE_COUNTER2_ELEMENT_SETCAPTURE_PAGE&min_channel_version=nightly%252F81&os=Windows_NT&processType=*&product=Firefox&sanitize=1&sort_by_value=0&sort_keys=submissions&start_date=2020-10-19&table=0&trim=1&use_submission_date=0

Comment 16

[Kagami Rosylight [:saschanaz] (they/them)]

I can see some actual uses of setCapture on GitHub: https://github.com/search?l=JavaScript&q=setCapture&type=Code

Particularly noVNC: https://github.com/novnc/noVNC/blob/0c4b3e802fe4415903467a52ccb1f630c318b385/core/util/events.js#L22

Comment 17

[Boris Zbarsky [:bzbarsky]]

The noVNC code polyfills it if not present, right? Would the polyfill work in Gecko?

Comment 18

[Emilio Cobos Álvarez (:emilio)]

Also a bunch of those uses seem like they make no assumption that the method exists, which is nice.

Comment 19

[Kagami Rosylight [:saschanaz] (they/them)]

Attachment: Bug 973604 - Mark set/releaseCapture() as deprecated r=annevk,edgar

Comment 20

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/df43273ec88c
Mark set/releaseCapture() as deprecated r=annevk,edgar

Comment 21

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/df43273ec88c

Comment 22

[Kagami Rosylight [:saschanaz] (they/them)]

The value reduced to 0.01% in Nightly 90 and now 0 in Nightly 91. Not sure what happened as noVNC hasn't change. Anyway, we can probably try disabling it on Nightly.

Comment 23

[BugBot [:suhaib / :marco/ :calixte]]

The leave-open keyword is there and there is no activity for 6 months.
:saschanaz, maybe it's time to close this bug?

Comment 24

[Kagami Rosylight [:saschanaz] (they/them)]

It's not hidden yet.

Comment 25

[Kagami Rosylight [:saschanaz] (they/them)]

The value reduced to 0.01% in Nightly 90 and now 0 in Nightly 91. Not sure what happened as noVNC hasn't change. Anyway, we can probably try disabling it on Nightly.

It's just because the telemetry item names are changed: https://telemetry.mozilla.org/new-pipeline/dist.html#!cumulative=0&end_date=2021-12-21&include_spill=0&keys=__none__!__none__!__none__&max_channel_version=nightly%252F97&measure=USE_COUNTER2_DEPRECATED_ElementSetCapture_PAGE&min_channel_version=nightly%252F81&os=Windows_NT&processType=*&product=Firefox&sanitize=1&sort_by_value=0&sort_keys=submissions&start_date=2021-12-06&table=0&trim=1&use_submission_date=0

Still 0.04%, nothing has changed.