Firefox 58 fails as before and user_pref trick does not work any more!! I installed 58 , rebooted and tested ~$ fgrep gfx. /home/cloudsto/.mozilla/firefox/ymtjpt2g.default-1510054306584-1514625894232/prefs.jsuser_pref("gfx.content.azure.backends", ""); user_pref("services.blocklist.gfx.checked", 1516706246); ~$ firefox -g GNU gdb (Ubuntu 8.0.1-0ubuntu1) 8.0.1 Copyright (C) 2017 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "arm-linux-gnueabihf". Type "show configuration" for configuration details. For bug reporting instructions, please see: . Find the GDB manual and other documentation resources online at: . For help, type "help". Type "apropos word" to search for commands related to "word"... Reading symbols from /usr/lib/firefox/firefox...Reading symbols from /usr/lib/debug/.build-id/dc/cf886d995205c45d42314d4e755178a87359d9.debug...done. done. (gdb) run Starting program: /usr/lib/firefox/firefox Cannot parse expression `.L1200 4@r4'. warning: Probes-based dynamic linker interface failed. Reverting to original interface. [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1". [New Thread 0xb18b0440 (LWP 1554)] [New Thread 0xadeb5440 (LWP 1555)] [Thread 0xadeb5440 (LWP 1555) exited] [New Thread 0xadeb5440 (LWP 1556)] [New Thread 0xacaff440 (LWP 1557)] [New Thread 0xac2ff440 (LWP 1558)] [New Thread 0xab9ff440 (LWP 1559)] [New Thread 0xab1ff440 (LWP 1560)] [New Thread 0xaafff440 (LWP 1561)] [New Thread 0xaadff440 (LWP 1562)] [New Thread 0xaabff440 (LWP 1563)] [New Thread 0xaa9ff440 (LWP 1564)] [New Thread 0xaa7ff440 (LWP 1565)] [New Thread 0xaa5ff440 (LWP 1566)] [New Thread 0xaa3ff440 (LWP 1567)] [New Thread 0xa9dff440 (LWP 1568)] [New Thread 0xa95ff440 (LWP 1569)] [New Thread 0xa8dff440 (LWP 1570)] [New Thread 0xa85ff440 (LWP 1571)] [New Thread 0xa7aff440 (LWP 1572)] [New Thread 0xa71ff440 (LWP 1574)] [New Thread 0xa7d97440 (LWP 1575)] [New Thread 0xa69ff440 (LWP 1576)] [Thread 0xa7aff440 (LWP 1572) exited] [New Thread 0xa7aff440 (LWP 1577)] [New Thread 0xa4cb6440 (LWP 1578)] [New Thread 0xa44b6440 (LWP 1579)] [New Thread 0xa3cb6440 (LWP 1580)] [New Thread 0xa321f440 (LWP 1581)] [New Thread 0xa2a1f440 (LWP 1582)] [New Thread 0xa221f440 (LWP 1583)] [New Thread 0xa1a1f440 (LWP 1584)] [New Thread 0xa0eda440 (LWP 1585)] [New Thread 0xa06b1440 (LWP 1586)] [New Thread 0x9feb1440 (LWP 1587)] [New Thread 0x9f6b1440 (LWP 1588)] [Thread 0x9f6b1440 (LWP 1588) exited] [Thread 0x9feb1440 (LWP 1587) exited] [Thread 0xa06b1440 (LWP 1586) exited] [New Thread 0xa06b1440 (LWP 1589)] [New Thread 0x9f6b1440 (LWP 1590)] [New Thread 0x9feb1440 (LWP 1591)] [New Thread 0x9e695440 (LWP 1592)] [New Thread 0x9de95440 (LWP 1593)] [New Thread 0x9d695440 (LWP 1594)] [New Thread 0x9ce95440 (LWP 1595)] [New Thread 0x9c695440 (LWP 1596)] [New Thread 0x9be95440 (LWP 1597)] [New Thread 0x9b4ff440 (LWP 1598)] [New Thread 0x9a1ff440 (LWP 1599)] [New Thread 0x999ff440 (LWP 1600)] [New Thread 0x989ff440 (LWP 1601)] [New Thread 0x98163440 (LWP 1602)] [New Thread 0xa71ff440 (LWP 1603)] [Thread 0xa71ff440 (LWP 1574) exited] [Thread 0xa71ff440 (LWP 1603) exited] [New Thread 0x977ff440 (LWP 1604)] [Thread 0x989ff440 (LWP 1601) exited] [New Thread 0x974ff440 (LWP 1605)] [New Thread 0x96aff440 (LWP 1606)] [Thread 0x98163440 (LWP 1602) exited] [New Thread 0x989ff440 (LWP 1607)] [Thread 0x974ff440 (LWP 1605) exited] [Thread 0x989ff440 (LWP 1607) exited] [New Thread 0x989ff440 (LWP 1608)] [New Thread 0x974ff440 (LWP 1610)] [New Thread 0x98163440 (LWP 1611)] Thread 1 "firefox" received signal SIGILL, Illegal instruction. 0xb3b7104e in _sk_xor__vfp4 () from /usr/lib/firefox/libxul.so (gdb) bt Python Exception Can't read data for section '.debug_loc' in file '/usr/lib/debug/.build-id/6d/64cb097d165b67c594143ed924556e1bfffa96.debug': #0 0xb3b7104e in _sk_xor__vfp4 () from /usr/lib/firefox/libxul.so (gdb) continue Continuing. ExceptionHandler::GenerateDump cloned child 1637 ExceptionHandler::SendContinueSignalToChild sent continue signal to child ExceptionHandler::WaitForContinueSignal waiting for continue signal... [Thread 0x98163440 (LWP 1611) exited] [Thread 0x974ff440 (LWP 1610) exited] [Thread 0x989ff440 (LWP 1608) exited] [Thread 0x96aff440 (LWP 1606) exited] [Thread 0x977ff440 (LWP 1604) exited] [Thread 0x999ff440 (LWP 1600) exited] [Thread 0x9a1ff440 (LWP 1599) exited] [Thread 0x9b4ff440 (LWP 1598) exited] [Thread 0x9be95440 (LWP 1597) exited] [Thread 0x9c695440 (LWP 1596) exited] [Thread 0x9ce95440 (LWP 1595) exited] [Thread 0x9d695440 (LWP 1594) exited] [Thread 0x9de95440 (LWP 1593) exited] [Thread 0x9e695440 (LWP 1592) exited] [Thread 0x9feb1440 (LWP 1591) exited] [Thread 0x9f6b1440 (LWP 1590) exited] [Thread 0xa06b1440 (LWP 1589) exited] [Thread 0xa0eda440 (LWP 1585) exited] [Thread 0xa1a1f440 (LWP 1584) exited] [Thread 0xa221f440 (LWP 1583) exited] [Thread 0xa2a1f440 (LWP 1582) exited] [Thread 0xa321f440 (LWP 1581) exited] [Thread 0xa3cb6440 (LWP 1580) exited] [Thread 0xa44b6440 (LWP 1579) exited] [Thread 0xa4cb6440 (LWP 1578) exited] [Thread 0xa7aff440 (LWP 1577) exited] [Thread 0xa69ff440 (LWP 1576) exited] [Thread 0xa85ff440 (LWP 1571) exited] [Thread 0xa8dff440 (LWP 1570) exited] [Thread 0xa95ff440 (LWP 1569) exited] [Thread 0xa9dff440 (LWP 1568) exited] [Thread 0xaa3ff440 (LWP 1567) exited] [Thread 0xaa5ff440 (LWP 1566) exited] [Thread 0xaa7ff440 (LWP 1565) exited] [Thread 0xaa9ff440 (LWP 1564) exited] [Thread 0xaabff440 (LWP 1563) exited] [Thread 0xaadff440 (LWP 1562) exited] [Thread 0xaafff440 (LWP 1561) exited] [Thread 0xab1ff440 (LWP 1560) exited] [Thread 0xab9ff440 (LWP 1559) exited] [Thread 0xac2ff440 (LWP 1558) exited] [Thread 0xacaff440 (LWP 1557) exited] [Thread 0xadeb5440 (LWP 1556) exited] [Thread 0xb18b0440 (LWP 1554) exited] [Thread 0xb6ff7010 (LWP 1515) exited] [Inferior 1 (process 1515) exited with code 04] (gdb) Details Add-ons: %7Bd10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d%7D:3.0.2,%7B73a6fe31-595d-460b-a920-fcc0f8843232%7D:10.1.6.3,disable-media-wmf-nv12%40mozilla.org:1.1,disable-js-shared-memory%40mozilla.org:2.0,aushelper%40mozilla.org:2.0,firefox%40getpocket.com:1.0.5,activity-stream%40mozilla.org:2017.11.07.1100-7f4e3634,formautofill%40mozilla.org:1.0,onboarding%40mozilla.org:1.0,screenshots%40mozilla.org:19.2.0,webcompat%40mozilla.org:1.1,shield-recipe-client%40mozilla.org:76.1,followonsearch%40mozilla.com:0.9.6,e10srollout%40mozilla.org:3.05,%7B972ce4c6-7e08-4474-a285-3208198ce6fd%7D:57.0.4,langpack-fi%40firefox.mozilla.org:57.0.4,langpack-en-GB%40firefox.mozilla.org:57.0.4,langpack-en-ZA%40firefox.mozilla.org:57.0.4 BuildID: 20180122231004 CrashTime: 1516788976 DOMIPCEnabled: 1 EMCheckCompatibility: true Email: