1628656 - Drag & drop events not fired in response design mode

Status: RESOLVED FIXED

(DevTools :: Responsive Design Mode, defect)

Description

[Ole Laursen]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Firefox/68.0

Steps to reproduce:

Drag & drop events are not fired properly in response design mode.

For instance, go to

https://developer.mozilla.org/en-US/docs/Web/API/Document/drag_event

Enable response design mode and scroll down and try to drag the "This div is draggable" div with the mouse.

Actual results:

The div is not moved.

Expected results:

The div should move around.

It looks like dragstart is fired, but the usual drag element shown by the browser does not show up.

Comment 1

[Virginia (please send need info request to Brindusa Tot)]

Hi Ole Laursen,

Thanks for reporting this bug.

I was able to reproduce it on Windows 10 and Ubuntu 18 LTS on Firefox Release and Beta versions.

However, issue is no longer happening on the latest Firefox Nightly. After investigating, I can see that a fix was applied as per bug 1621306.

When Firefox Release version reaches 77, the issue will no longer be present. This is expected to be shipped on 2020-06-02.

You can follow up the release schedule on this link: https://wiki.mozilla.org/Release_Management/Calendar

I'm attaching the result of the mozregression where I found the applied fix:
2020-04-15T15:18:53: INFO : platform_changeset: 5f7ee717b8528804347cbb2e877865a3e34d6991
2020-04-15T15:18:53: INFO : platform_repository: https://hg.mozilla.org/integration/autoland
2020-04-15T15:18:53: INFO : platform_version: 76.0a1
2020-04-15T15:19:20: INFO : Narrowed inbound regression window from [7516aaa5, 29f9f745] (3 builds) to [7516aaa5, 5f7ee717] (2 builds) (~1 steps left)
2020-04-15T15:19:20: DEBUG : Starting merge handling...
2020-04-15T15:19:20: DEBUG : Using url: https://hg.mozilla.org/integration/autoland/json-pushes?changeset=5f7ee717b8528804347cbb2e877865a3e34d6991&full=1
2020-04-15T15:19:22: DEBUG : Found commit message:
Bug 1621306 - Enable the devtools.responsive.browserUI.enabled pref in Nightly only r=bradwerth

Differential Revision: https://phabricator.services.mozilla.com/D66246

2020-04-15T15:19:22: DEBUG : Did not find a branch, checking all integration branches
2020-04-15T15:19:22: INFO : The bisection is done.
2020-04-15T15:19:22: INFO : Stopped

I'll be marking this ticket as resolved. If the issue is still reproducible with the latest Firefox Nightly version, feel free to reopen the bug with more information.

Regards,
Virginia

Comment 2

[Rares Doghi, Desktop QA]

The fix for this issue will eventually reach Release, i'm adding myself to the cc of this issue so we can double check that its fixed then as well.