Remove about:buildconfig. If used as-is, it would add unnecessary runtime dependencies. diff -ur firefox-65.0-orig/docshell/base/nsAboutRedirector.cpp firefox-65.0/docshell/base/nsAboutRedirector.cpp --- firefox-76.0.orig/docshell/base/nsAboutRedirector.cpp 2020-05-03 19:01:29.926544735 +0200 +++ firefox-76.0/docshell/base/nsAboutRedirector.cpp 2020-05-03 19:12:00.845035570 +0200 @@ -62,8 +62,6 @@ {"about", "chrome://global/content/aboutAbout.html", 0}, {"addons", "chrome://mozapps/content/extensions/extensions.xhtml", nsIAboutModule::ALLOW_SCRIPT}, - {"buildconfig", "chrome://global/content/buildconfig.html", - nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT}, {"checkerboard", "chrome://global/content/aboutCheckerboard.html", nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT | nsIAboutModule::ALLOW_SCRIPT}, diff -ur firefox-65.0-orig/toolkit/content/jar.mn firefox-65.0/toolkit/content/jar.mn --- firefox-65.0-orig/toolkit/content/jar.mn 2019-01-23 00:48:35.033372506 +0100 +++ firefox-65.0/toolkit/content/jar.mn 2019-01-23 00:50:45.126565924 +0100 @@ -36,7 +36,6 @@ content/global/plugins.css content/global/browser-child.js content/global/browser-content.js -* content/global/buildconfig.html content/global/buildconfig.css content/global/contentAreaUtils.js content/global/datepicker.xhtml