User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.99 Safari/537.36 Steps to reproduce: open https://dev.alisgames.com:8081/hero/data-single_test/hero_test.html click on video to skip, wait until game is loading Actual results: text are not draw correct (some text are not draw at all). Firefox 34 works fine. Chrome and Safari works fine Expected results: text must be drawn as on attached image (from chrome, in safari works too)

forget to write, all texts are rendered into texture and then texture with whole text is drawn to screen. It seems that first batch is not drawn correct the second one seems to draw correct

that is how it works in firefox

porbably the cause is that I'm using alpha texture (i.e. texture that has only alpha channel glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, (GLsizei)image.getWidth(), (GLsizei)image.getHeight(), 0, GL_ALPHA, GL_UNSIGNED_BYTE, image.getData());

Could you provide minimal testcase? And could you try using mozregression tool to find regression? ( http://mozilla.github.io/mozregression/ )

from mozregression 11:21.94 LOG: MainThread Bisector INFO Last good revision: 14665b1de5ee 11:21.94 LOG: MainThread Bisector INFO First bad revision: 5d6ec4dddf14 11:21.94 LOG: MainThread Bisector INFO Narrowed nightly regression window from [2014-09-30, 2014-10-02] (2 days) to [2014-10-01, 2014-10-02] (1 days) (~0 steps left) creating more minimal test require for me quite a lot of time. If mozreggression info is not enough tell me.

Pushlog in accordance with comment #5 https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=14665b1de5ee&tochange=5d6ec4dddf14 Suspect: Bug 1048108

Disable ANGLE helps. (however, another Bug 1123573 will raise) user_pref("webgl.disable-angle", true); user_pref("webgl.force-enabled", true);

these changes user_pref("webgl.disable-angle", true); user_pref("webgl.force-enabled", true); helps. I found workaroud without changing prefs. I need to explicitly define when initialize webgl context. alpha:true e.g. var webGLContextAttributes = {alpha:true}; ctx = canvas.getContext("webgl", webGLContextAttributes) || canvas.getContext("experimental-webgl", webGLContextAttributes); However this is default value

This might be a windows-specific regression, I can't reproduce it on linux on firefox 35.

Related bug from AlteredQualia: https://bugzilla.mozilla.org/show_bug.cgi?id=1124187