Dragging tabs across OSX desktops causes unusual behavior




6 years ago
5 years ago


(Reporter: mhoye, Unassigned)


Firefox Tracking Flags

(Not tracked)




6 years ago
Dragging a tab from one maximized window to another across desktops in OSX causes some pretty severe wierdness. Symptoms include, but are not limited to:

- Disappearing windows (blank desktops, no Nightly visible)
- Dragging a tab onto itself now causes the window to jump down, revealing the textured OSX background
- Windows rendering, flickering, and then disappearing again.

This is on Nightly.
Component: Tabbed Browser → Widget: Cocoa
Product: Firefox → Core
Any idea when this started?

For example does this happen with FF 21, or with FF 20?

Which version of OS X are you on?

Comment 2

6 years ago
I don't have a regression range yet, but I can't reproduce in a  Aurora or FF-release. I'm using an up-to-date OSX 10.8.3.
How *do* you drag a tab across "desktops" (or "screens")?

I just tried (on OS X 10.7.5), but can't figure out how.
Flags: needinfo?(mhoye)
OK, I've now figured out a way to drag a tab from a Firefox window on one "screen" to another Firefox window on a different "screen".  But it works just fine on both OS X 10.7.5 and 10.8.3, in both FF 21 and today's mozilla-central nightly, and between windows that are both "normal" sized, both maximized, and even both full-screen.

1) Open two Firefox windows, and open an extra tab in one of them (I visited https://www.mozilla.org/en-US/ in that extra tab).
2) Use Mission Control to move one of those windows to a different "space".
3) In the "space" whose FF window has the extra tab, drag that tab down to Mission Control in the Dock.
4) Wait until Mission Control flashes a couple of times and you see its multi-screen view.
5) Keep dragging the tab until it's over the screen containing the other FF window.
6) Wait until that screen flashes a couple of times and you get a single-screen view of the screen containing the other FF window.
7) Keep dragging the tab until you seen the "tab drop" icon in the other FF window's tab bar.
8) Let go the mouse button.  The tab should get added to the other FF window.
By any chance do you have multiple monitors, and are you dragging tabs from one monitor to the other?

Comment 6

6 years ago
This works on a single monitor setup. First example is: Maximize firefox, open several tabs in it and drag one of them off the side of the screen, into its own desktop. Observe as things go sideways.

Next step is: Maximize two separate firefox windows, and drag a tab from one to the other. Also, things go sideways.

I wonder if I can do a screen recording of this?
Flags: needinfo?(mhoye)
> drag one of them off the side of the screen, into its own desktop

I didn't know you could do this.  But once again I tried it, and had no problems.  (I tested with today's mozilla-central nightly on OS X 10.8.3.)

Understand that dragging (or doing anything) across desktops uses Apple's Mission Control app.  So (for example) you can accidentally drag stuff into the Dashboard desktop.  And you can only drag stuff to desktops you've already "created" in Mission Control.

Have you customized Mission Control in some way?

Also, do these problems happen with a clean profile?

Comment 8

5 years ago
I haven't been able to replicate this in a long time, despite my best efforts, so I can't justify leaving it open. Marking resolved WFM, thanks everyone.
Last Resolved: 5 years ago
Resolution: --- → WORKSFORME
You need to log in before you can comment on or make changes to this bug.