When I open arrow panels, any of the Larry button, the downloads button or the social API toolbar items, the panels flicker. It's as if the panel opens and then closes and then re-opens in a fraction of a second. I believe this is a core arrow panel problem because I'm seeing it across various arrow panels. Tested latest nightly build on Windows This seems like a regression to me.

Does this only happen when you click the button triggering the panel repeatedly?

Jared: can you reproduce this? I'm away from Windows for a bit...

I can't reproduce it on Win7 9/18 Nightly. I tried clicking very quickly on the identity button and downloads panel button.

I can reproduce it with one normal click almost 100% of the time with the Larry button, the download button, and the social buttons.

I can't see this with one normal click. It looks to me like the panels actually slide down to show the anchor arrow and there may even be a fade-in effect as it opens and a fade-out effect when it closes. If I quickly click multiple times, it looks like I just see an artifact of this sliding/fading rather than actual flicker. Asa, assuming the fading is actually done, I wonder if it could be related to your graphics driver or similar, and if it is worth running around to a few other Windows machines and see if they exhibit the same behavior?

This could indeed be related to bug 767861 (landed for Firefox 16) or bug 767133 (Firefox 17), and may be dependent on a specific graphics configuration. Asa, do you see this in Beta/Aurora?

(In reply to :Gavin Sharp (use gavin@gavinsharp.com for email) from comment #6) > This could indeed be related to bug 767861 (landed for Firefox 16) or bug > 767133 (Firefox 17), and may be dependent on a specific graphics > configuration. > > Asa, do you see this in Beta/Aurora? This works fine in Beta and Aurora. It fails for me in nightly. My graphics info: Adapter Description: Intel(R) HD Graphics 4000 Adapter Drivers: igdumd64 igd10umd64 igd10umd64 igdumd32 igd10umd32 igd10umd32 Adapter RAM: Unknown ClearType Parameters: Gamma: 2200 Pixel Structure: RGB ClearType Level: 100 Enhanced Contrast: 50 Device ID: 0x0166 Direct2D Enabled: true DirectWrite Enabled: true (6.1.7601.17789) Driver Date: 3-19-2012 Driver Version: 8.15.10.2696 GPU #2 Active: false GPU Accelerated Windows: 1/1 Direct3D 10 Vendor ID0x8086 WebGL Renderer: Google Inc. -- ANGLE (Intel(R) HD Graphics 4000) -- OpenGL ES 2.0 (ANGLE 1.0.0.1267) AzureCanvasBackend: direct2d AzureContentBackend: direct2d AzureFallbackCanvasBackend: cairo

FWIW, the second display adapter on my desktop box has an almost identical graphics configuration, and having nightly open on that adapter doesn't show any evidence of flicker. "graphics": { "numTotalWindows": 2, "numAcceleratedWindows": 2, "windowLayerManagerType": "Direct3D 10", "adapterDescription": "NVIDIA GeForce 8400 GS ", "adapterVendorID": "0x10de", "adapterDeviceID": "0x0422", "adapterRAM": "256", "adapterDrivers": "nvd3dumx,nvwgf2umx,nvwgf2umx nvd3dum,nvwgf2um,nvwgf2um", "driverVersion": "8.17.13.142", "driverDate": "5-15-2012", "adapterDescription2": "Intel(R) HD Graphics 4000", "adapterVendorID2": "0x8086", "adapterDeviceID2": "0x0162", "adapterRAM2": "Unknown", "adapterDrivers2": "igdumd64 igd10umd64 igd10umd64 igdumd32 igd10umd32 igd10umd32", "driverVersion2": "8.15.10.2696", "driverDate2": "3-19-2012", "isGPU2Active": false, "direct2DEnabled": true, "directWriteEnabled": true, "directWriteVersion": "6.1.7601.17789", "clearTypeParameters": "DISPLAY1 [ Gamma: 2200 Pixel Structure: RGB ClearType Level: 100 Enhanced Contrast: 50 ] DISPLAY2 [ Gamma: 2200 Pixel Structure: RGB ClearType Level: 100 Enhanced Contrast: 50 ] DISPLAY3 [ Gamma: 2200 Pixel Structure: RGB ClearType Level: 100 Enhanced Contrast: 50 ] ", "webglRenderer": "Google Inc. -- ANGLE (NVIDIA GeForce 8400 GS ) -- OpenGL ES 2.0 (ANGLE 1.0.0.1267)", "info": { "AzureCanvasBackend": "direct2d", "AzureFallbackCanvasBackend": "cairo", "AzureContentBackend": "direct2d" }

Here's a video demonstrating the problem: http://youtu.be/0oDc4A4ARnU

It only happens for Nvidia graphics driver. I have personally tested on 1 with nvidia, 1 with ati , and one without any . All latest Nightlies, Windows 7. So if I disable HWA, it gets fixed

Since 27-10-2012 build I can't reproduce this bug anymore. I'm not sure if this has been fixed by something in Firefox, or by recent WDDM update.

I can reproduce it every single time, both with 27-10-12 and 28-10-12

I was able to reproduce the same bug on common popups (like a folder of bookmarks on the toolbar), and likely this is a graphics bug, something similar happened in the past already (I'm sure I had the problem, then a graphics patch fixed it, then some time later it started again, unfortunately I don't remember the bug #). Fwiw, I also have an nVidia card. What flickers is not the panel, it's the selection. This could have been confused with a downloads panel bug that caused it to quickly open twice and is now fixed. Plus panels have larger selections, so it's more noticeable there. Considering all of this, for how much I hate when this happens, this is not going to be a downloads panel blocker. It's likely not even a snappy issue, it's mostly a graphical (acceleration) glitch.

(In reply to Marco Bonardo [:mak] from comment #14) > What flickers is not the panel, it's the selection. This could have been > confused with a downloads panel bug that caused it to quickly open twice and > is now fixed. Plus panels have larger selections, so it's more noticeable > there. What do you mean by the selection flickers ? I am pretty sure the at least for the case of arrow-panels, its the panel that quickly animates out twice in the same time it was supposed to animate once. On noticing carefully, one can see that the second time the panel appears, there is already a panel behind that gets hidden..

(In reply to Girish Sharma [:Optimizer] from comment #15) > I am pretty sure the at least for the case of arrow-panels, its the panel > that quickly animates out twice in the same time it was supposed to animate > once. As I said, the downloads panel had such a bug that is now fixed, to not be confused with the additional flickering I see there.

I'm seeing this "flicker" on current Nightly (OS X) with the Social (Facebook Messenger) panels - friend requests, messages, notifications - although I am -not- seeing it with the Downloads panel. When opening the various Social panels in turn, I can see that what appears in the initial momentary flash is the content of the -previously-viewed- panel (but in the new location); then it is replaced by the correct content of the new panel. Repeatedly opening the -same- panel, therefore, flickers because of the repeated animate-into-view (at least that's what it looks like), but the content of the initial flash and the eventual display is the same.

I also see the same behavior as mentioned by Jonathan above. I see it for both Downloads panel and Social Panels. Basically on every arrow panel. This only happens with Hardware Acceleration enabled on Windows 7 (no idea about other OS) but it does not happen when I disable HWA on Windows 7. Can this bug be please looked into ? It is affecting a very large number of users.

Moving to Core:XUL per https://bugzilla.mozilla.org/show_bug.cgi?id=1455336