Steps To Reproduce: 1. Click "Change Search Setting" from SearchBar to open Search in-content preferences 2. Click "Content" and then click "Search" to toggle pane of in-content preferences 3. Click Maximize button of window contorols at the top-right window Actual Results: Browser hangs

OR Steps To Reproduce: 1. Maximized browser and restart 2. Click Restore button of window contorols at the top-right window 3. Click "Change Search Setting" from SearchBar to open Search in-content preferences 4. Click Maximize button of window contorols at the top-right window Actual Results: Browser hangs

I am tested in non-e10s window.

[Tracking Requested - why for this release]:

Stack using crashfirefox.exe : bp-0ad2d70d-4760-4c78-bfd6-357ac2141218

The hang happens with a high probability when I perform steps in Comment#0 and/or Comment#1. Pushlog: https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=2a61df4eaa2d&tochange=24ba8274ed60

Not rerated to "Search" pane. Just open in-content preferencesor about:config.

And, The hang seems to occur only in Windows7 Classic style.

And, also in Windows7 Basic style.

Graphics -------- Adapter Description: AMD Radeon HD 6450 Adapter Drivers: aticfx64 aticfx64 aticfx64 aticfx32 aticfx32 aticfx32 atiumd64 atidxx64 atidxx64 atiumdag atidxx32 atidxx32 atiumdva atiumd6a atitmm64 Adapter RAM: 1024 ClearType Parameters: Gamma: 2200 Pixel Structure: R ClearType Level: 100 Enhanced Contrast: 200 Device ID: 0x6779 Direct2D Enabled: true DirectWrite Enabled: true (6.2.9200.16571) Driver Date: 11-20-2014 Driver Version: 14.501.1003.0 GPU #2 Active: false GPU Accelerated Windows: 1/1 Direct3D 11 (OMTC) Subsys ID: 23111787 Vendor ID: 0x1002 WebGL Renderer: Google Inc. -- ANGLE (AMD Radeon HD 6450 Direct3D11 vs_5_0 ps_5_0) windowLayerManagerRemote: true AzureCanvasBackend: direct2d 1.1 AzureContentBackend: direct2d 1.1 AzureFallbackCanvasBackend: cairo AzureSkiaAccelerated: 0

in local build Last Good: 2a61df4eaa2d First Bad: 823227372483 Regressed by: 823227372483 Bas Schouten — Bug 1107297: Only recomposite the damaged rect with D3D11. r=jrmuizel This patch makes us behave similarly to when we're using the BasicCompositor, essentially we will clip all drawing to the final display to the area that was labeled as invalid. When DXGI 1.2 is available we will then also report the damaged area to the Present call so that can then be used to minimize the amount of bits that actually need to be blitted to the screen. Since we're no longer recompositing the whole screen this means we should also only clear the damaged area of the window.

WORKAROUND: Enable TitleBar

Toggle "Show desktop" button(on the button at the far right end of the taskbar) helps. So, The problem isthat Nightly37 does not correctly update own window. This is very annoyance.

[Tracking Requested - why for this release]:

Bas, Can you look at this?

This seems ro be fixed by Bug 1117925 in m-c

s/ro/to

Confirmed it fixed https://hg.mozilla.org/mozilla-central/rev/06b590bf59f4 Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Firefox/38.0 ID:20150121141530