Concerning debug assertions in the font patch
While trying to get to the bottom of the latest round of TBB crash bugs, gk noticed these assertions that were seemingly introduced in debug builds:
###!!! ASSERTION: bad font face url passed to fontloader: 'aFontFaceSrc && !aFontFaceSrc->mIsLocal', file /home/firefox64/TBB/CrashFontDebug/mozilla-esr17/layout/style/nsFontFaceLoader.cpp, line 809 ###!!! ASSERTION: null font uri: 'aFontFaceSrc->mURI', file /home/firefox64/TBB/CrashFontDebug/mozilla-esr17/layout/style/nsFontFaceLoader.cpp, line 810
He wrote this in https://trac.torproject.org/projects/tor/ticket/8939#comment:1:
"This does neither happen with a vanilla Firefox (+ the Tor Browser .mozconfig) nor a patched Firefox without the patch 0011. Looking a bit deeper then 2a543b9359029938dfa98f8e285fb5528104d527 is still okay but b0e19e9a7e94dcbd6e50ea3739c5b3ce218fe57c is not anymore. Thus, this seems to be a bug in the fix for #8455 (closed) and probably responsible for all the crash bugs that showed up recently..."
We later discovered it was not responsible for the majority (or any?) of the crash bugs, but it certainly should be investigated.