1431663 - Browser freezes when trying to drag a file from the Downloads-list to a local folder.

Status: RESOLVED INVALID

(Firefox :: Downloads Panel, defect)

Description

[u543021]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20180104101725

Steps to reproduce:

Using Firefox in Ubuntu 17.10:

1. Download a file
2. Open the Download-dropdown (by default in the top right corner of the browser)
3. Drag the file to a folder on your computer (nautilus)


Actual results:

The browser freezes (the cursor is stuck in the dragging-icon, music in the browser keeps playing but nothing is clickable etc).


Expected results:

The file should be moved to the folder you are dragging it into.

Comment 1

[:Paolo Amadini]

For this to be actionable we would need a performance profile from the reporter, but their Bugzilla account is currently disabled.

Comment 2

[laurens]

(In reply to :Paolo Amadini from comment #1)
> For this to be actionable we would need a performance profile from the
> reporter, but their Bugzilla account is currently disabled.

I'm the reporter (didn't know I could change my nickname so removed the whole account.. :P).
How do I create/send a performance profile?

Comment 3

[:Paolo Amadini]

Hi, thanks for getting back to us! There is a guide on how to create a profile here:

https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Reporting_a_Performance_Problem

If the browser always freezes during drag and drop, the issue should be easy to capture. Let me know if you have any questions.

Comment 4

[laurens]

Okay I've got more info.

The problem occurs when I try to drag an image OR link (from the URL-bar) to a folder-window in Ubuntu (when I try to drag something to the desktop, everything works fine). Firefox freezes, and sometimes when dragging/resizing the window a bit it unstucks and works again, however this seems random behaviour. When I use the keyboard shortcut to view the desktop (Super + D), the desktop is shown yet the holding cursor is still active and I'm unable to click anything on the desktop. When I kill the firefox process, everything works again.

Performance Profile: https://perfht.ml/2rVtxlD

Is this alright?
Thanks for the help!

Comment 5

[:Paolo Amadini]

That's really valuable information, thanks!

From the performance profile and the rest of comment 4, it seems that Firefox is spending most of the time waiting for the operating system to dispatch mouse or keyboard events, but once the event arrives, it is processed without delay.

In other words, it seems the process itself is not blocked, but it's not possible to interact with it, which is in line with the fact that it's also difficult to interact with other applications like the Desktop. It seems this might be a bug with the implementation of file drag-and-drop in the system, rather than Firefox.

Florian, did I interpret the profile correctly?

Comment 6

[Florian Quèze [:florian]]

(In reply to :Paolo Amadini from comment #5)

> From the performance profile and the rest of comment 4, it seems that
> Firefox is spending most of the time waiting for the operating system
> […] It seems
> this might be a bug with the implementation of file drag-and-drop in the
> system, rather than Firefox.

I agree.

Comment 7

[:Paolo Amadini]

Thanks Florian, I don't think there's much more we can do here.

laurens, thank you a lot for reporting the issue and doing the profiling! The next step might be to file a bug in the tracker of your distribution. Feel free to reference this report and profile if needed.