I think I hit this issue several times on Gentoo although not using x11-themes/gtk-engines-murrine with seamonkey or firefox. Quoting from https://bugs.freedesktop.org/show_bug.cgi?id=78787#c12 Vlad Orlov (monsta) wrote on 2016-06-14: #10 [Impact] Due to a problem in the Murrine engine, using bitmap fonts and Murrine-based themes at the same time might lead to crash of various GTK+2 apps. This issue was around for about 3-4 years, or maybe even more. It affects a lot of Xfce and MATE users who choose to use bitmap fonts, and it's present in two current LTS releases, so it would be really nice to apply the fix there. The patch which is posted below fixes the crashes for good and allows people to use bitmap fonts and Murrine-based themes together again. [Test Case] Steps to reproduce: 1. Have Xubuntu (or Xfce in any other Ubuntu edition) installed. It can be any release from 14.04 to 16.10. 2. Install gtk2-engines-murrine, murrine-themes and shimmer-themes packages, if they're not installed. 3. Install some package with bitmap fonts, for example, xfonts-terminus. 4. Run xfce4-appearance-settings and select some Murrine-based theme, for example, Greybird or Murrine-Light. 5. Switch to the Fonts tab and select some bitmap font, for example, Terminus. 6. Exit xfce4-appearance-settings. Now some GTK+2 apps will crash right on start with the following error message: ../../../../src/cairo-scaled-font.c:459: _cairo_scaled_glyph_page_destroy: Assertion `!scaled_font->cache_frozen' failed. It's reproducible with mousepad, gimp, geany. With some Murrine-based themes, like Greybird, it's also reproducible with xfce4-panel and Xfce configuration apps: xfce4-appearance-settings, xfce4-mouse-settings, xfce4-session-settings, etc. It also affects some MATE apps, like mate-panel or mate-control-center. [Regression Potential] After several months of testing the fix in Debian Jessie and a few Ubuntu releases, I hadn't found any regressions. Since the patch is very small and it fixes all the crashes for good, I don't think there's much space for the regressions. [Other Info] Appearance settings being affected is a nasty thing. However, you can reset the font to default via the console tool: $ xfconf-query -c xsettings -p /Gtk/FontName -r The patch was made following the proposed solution at: https://bugs.freedesktop.org/show_bug.cgi?id=78787#c9 https://bugs.launchpad.net/ubuntu/+source/gtk2-engines-murrine/+bug/1294699/+attachment/4683414/+files/murrine-ubuntu-debdiff
This looks like a runtime problem. Please provide software versions and steps how to reproduce this problem in Gentoo, not Xubuntu.
I reported this in the past in Mozilla's bugzilla (see URL above). You know from my other reports that I don't have binaries with debug info. In Gentoo bugzilla you can my find reports how to prevent CFLAGS forcing -O and -O2 but they were rejected. So, with this bug report I wanted to bring this to you attention, the referenced URL (see above) shows I hit this with a seamonkey-2.39 compiled on Gentoo against x11-libs/cairo-1.14.2-r1. Try to reproduce this on your own, I believe the description of the problem could help you to narrow the tests. For me were semonkey-2.39 self-compiled on my gentoo unstable so I switched to upstream's 64 bt linux binaries. They are stable on my Gentoo.
In the future, please clearly indicate in the bug summary what package you are reporting a bug against. Otherwise, it is likely to sit for weeks in the unassigned queue.
If you feel I have closed your bug and it is still a current issue, please reopen and update it completely. We will not work bugs that have no ebuild in tree any longer or can not be reproduced with a current system. Thank You for your support and understanding The Mozilla Team
