User Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:30.0) Gecko/20100101 Firefox/30.0 (Beta/Release) Build ID: 20140312030201 Steps to reproduce: Start the Nightly version of Fx. Visit some web sites to make active the Back/Forward buttons. Actual results: Forward button top border seems too light, while the bottom border is almost invisible. Expected results: Forward button borders should be displayed better.

Graphics -------- Adapter Description: AMD Radeon HD 7900 Series Adapter Drivers: aticfx64 aticfx64 aticfx64 aticfx32 aticfx32 aticfx32 atiumd64 atidxx64 atidxx64 atiumdag atidxx32 atidxx32 atiumdva atiumd6a atitmm64 Adapter RAM: 3072 Device ID: 0x6798 Direct2D Enabled: true DirectWrite Enabled: true (6.3.9600.16384) Driver Date: 2-23-2014 Driver Version: 13.350.1005.0 GPU #2 Active: false GPU Accelerated Windows: 1/1 Direct3D 11 (OMTC) Vendor ID: 0x1002 WebGL Renderer: Google Inc. -- ANGLE (AMD Radeon HD 7900 Series Direct3D9Ex vs_3_0 ps_3_0) windowLayerManagerRemote: true AzureCanvasBackend: direct2d AzureContentBackend: direct2d AzureFallbackCanvasBackend: cairo AzureSkiaAccelerated: 0

I just ran Nightly Fx30 under a VM and I don't see this problem. I'm guessing it might be a video card issue. My VM uses a virtual generic video card. I use an AMD HD7970. I also tried with HWA and OMTC off but that didn't work.

Just nailed it down. It's a HiDPI issue. I run at 120 DPI. I set layout.css.devPixelsPerPx = 1.0 which gives me 96dpi in Fx and the borders are fine.

Gary are you still seeing this on recent versions of Firefox?

Buttons look fine. Time to close this.

Thanks!