1911423 - Can't scroll map well with touchpad on https://www.lmiamap.com/ due to the site using a DOMMouseScroll listener

Status: ASSIGNED

(Web Compatibility :: Site Reports, defect, P3)

Description

[Timothy Nikkel (:tnikkel)]

Try to zoom in on the map using a scroll gesture (on macbook touchpad for example). Try to scroll the page. Try to zoom out on the map. Chrome behaves better.

Comment 1

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

The severity field is not set for this bug.
:botond, could you have a look please?

For more information, please visit BugBot documentation.

Comment 2

[Botond Ballo [:botond]]

(In reply to Timothy Nikkel (:tnikkel) from comment #0)

Try to zoom in on the map using a scroll gesture (on macbook touchpad for example). Try to scroll the page. Try to zoom out on the map. Chrome behaves better.

This description is pretty vague. I'm going to try to make it more specific based on the behaviour I'm seeing on the page. Let me know if I've misunderstood.

Steps to reproduce

1. Load https://www.lmiamap.com/
2. Position the cursor over the map
3. Perform a touchpad scroll gesture downward

Expected results

The map is zoomed out. The page does not scroll down.

This is what is observed in Chrome.

Actual results

The map is zoomed out and the page scrolls down.

This happens somewhat intermittently; it seems to happen more often when the speed of the touchpad scroll is slow.

Comment 3

[Botond Ballo [:botond]]

In Firefox, the <div class="MicrosoftMap" ...> element has a DOMMouseScroll event listener, and no wheel event listener. In Chrome, it has a wheel event listener (and no DOMMouseScroll event listener).

These sort of issues are expected with DOMouseScroll, a fundamentally broken non-standard feature that sites should not be using (see bug 1705584 for some analysis).

Comment 4

[Thomas Wisniewski [:twisniewski][PTO August 18-22]]

I can't zoom with my trackpad at all on my macbook on the site. They are using a Power BI map, which relies on the mousewheel event. An actual mouse wheel is still working, however, and Android seems to pinch-zoom fine, which means we should be able to ship a desktop-only intervention here which essentially re-maps wheel events to mousewheel convincingly enough for Power BI (I have one in-progress which seems to work fine).

Comment 5

[Thomas Wisniewski [:twisniewski][PTO August 18-22]]

Attachment: Bug 1911423 - add a desktop-only JS intervention for Power BI maps to fix touchpad zooming; r?denschub

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/0eacffbca3e1
add a desktop-only JS intervention for Power BI maps to fix touchpad zooming; r=denschub,webcompat-reviewers

Comment 7

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/0eacffbca3e1

Comment 8

[Thomas Wisniewski [:twisniewski][PTO August 18-22]]

www.lmiamap.com seems to have expired now, making it impossible to know if this intervention is still needed (since I'm sure there are other powerbi apps using maps like it did). I'll keep the intervention for now, and will monitor to see if lmiamap comes back sometime, otherwise we might just need to speculatively keep the intervention active, without knowing whether it still actually fixes anything.