User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.3a4pre) Gecko/20100330 Minefield/3.7a4pre ID:20100330035832 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.3a4pre) Gecko/20100330 Minefield/3.7a4pre ID:20100330035832 Enable 2d2 and dw, and "Classic" window style. Border of Back button is ugly Reproducible: Always Steps to Reproduce: 1. Select "Classic" window style. 2. Start Minefield with clean profile and enabled d2d and dw. Actual Results: Border of Back button is ugly. It seems to be a polygon, and the shadow is not beautiful, too Expected Results: It should be as of disable d2d/dw regression range: works: http://hg.mozilla.org/mozilla-central/rev/f9e4da420fbf Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.3a4pre) Gecko/20100326 Minefield/3.7a4pre ID:20100326221643 fails: http://hg.mozilla.org/mozilla-central/rev/82d527d82812 Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.3a4pre) Gecko/20100327 Minefield/3.7a4pre ID:20100327002738 pushlog: http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=f9e4da420fbf&tochange=82d527d82812 candidate bug: Bug 554662 - Further Tweaks to Toolbar Buttons

this happens on not only "Classic" but also "Aero peek"