Thanks a lot for the long and accurate answer! I agree that the problem probably is in some strange interaction between versions ... in a system that is the result of years of upgrade+dist-upgrade. The solution could be taking one day to rebuild it from scratch ... hoping one day is enough! :-) Let's try a last time.
May be at a glance you see something strange!? Giorgio (my answers below) I currently tend to think there is something fishy within your system, > maybe something miss configured or package version mixed up, you've > written about some external included sources. > Thanks for the kind and complete answer! I currently tend to think there is something fishy within your system, > maybe something miss configured or package version mixed up, you've > written about some external included sources. > The external packages are only few, I exclude this could be the problem. They are: - epoptes-client: 22.01-1+202208211647~ubuntu20.04.1 from http://ppa.launchpad.net/ltsp/ppa/ubuntu focal/main amd64 Packages - google-drive-ocamlfuse: 0.7.27-0ubuntu1~ubuntu16.04.1 from http://ppa.launchpad.net/alessandro-strada/ppa/ubuntu xenial/main amd64 Packages - google-chrome-stable: 105.0.5195.52-1 from http://dl.google.com/linux/chrome/deb stable/main amd64 Packages It's quite impossible to debug anything from a remote side as your local > system is like a black box for others as there is nothing really known > except the information you are using XFCE on a sid system. There is no > knowledge about used versions of the various packages. > I've installed reportbug and sent info from there ... they will appear in this tread (I hope). Some side note about the pre-compiled upstream TB versions, they come > with all required libraries included, so it's not really something > special that these versions are "really" working. This excludes a BUG in TB itself. NOTE: also pre-compiled fails when I run it in my "testing" station. The menu Help provides some entries which can be used to get more > information about the current profile and processes and used modules. > Compare the output. > > In most cases the JS console helps to find out what missing or not fully > working. > I' paste from the JS console ... This page is in Quirks Mode. Page layout may be impacted. For Standards Mode use “<!DOCTYPE html>”. hiddenWindow.html This page is in Quirks Mode. Page layout may be impacted. For Standards Mode use “<!DOCTYPE html>”. AddonRepository.jsm:97:12 Trying to load /usr/lib/thunderbird/libotr.so OTRLib.jsm:64:11 Trying to load libotr.so from system's standard library locations OTRLib.jsm :64:11 Trying to load libotr.so.5 from system's standard library locations OTRLib.jsm:64:11 Trying to load libotr.so from system's standard library locations OTRLib.jsm :64:11 Error: Cannot load required OTR library loadExternalOTRLib resource:///modules/OTRLib.jsm:109 init resource:///modules/OTRLib.jsm:115 once resource:///modules/OTR.jsm:117 init resource:///modules/OTR.jsm:138 init resource:///modules/OTRUI.jsm:255 OTR.jsm:126:15 Successfully loaded OpenPGP library librnp.so.0 version 0.16.0-1 from system's standard library locations RNPLib.jsm:100:15 RangeError: invalid language tag: "it-IT-euro" mozIntl.jsm:866:24 Uncaught (in promise) Exception { name: "NS_ERROR_XPC_JAVASCRIPT_ERROR_WITH_DETAILS", message: "[JavaScript Error: \"invalid language tag: \"it-IT-euro\"\" {file: \"resource://gre/modules/mozIntl.jsm\" line: 866}]'[JavaScript Error: \"invalid language tag: \"it-IT-euro\"\" {file: \"resource://gre/modules/mozIntl.jsm\" line: 866}]' when calling method: [mozIMozIntl::getCalendarInfo]", result: 2153185313, filename: "resource:///modules/calendar/utils/calL10NUtils.jsm", lineNumber: 66, columnNumber: 0, data: XPCWrappedNative_NoHelper, stack: "_calendarInfo @resource:///modules/calendar/utils/calL10NUtils.jsm:66:30\ nsetLocaleDefaultPreferences @chrome://calendar/content/calendar-chrome-startup.js:318:31\ nloadCalendarComponent @chrome://calendar/content/calendar-chrome-startup.js:50:3\n", location: XPCWrappedNative_NoHelper } calL10NUtils.jsm:66 Found 0 public keys and 0 secret keys (0 protected, 0 unprotected) RNPLib.jsm:301:15 services.settings: Failed to load last_modified.json: TypeError: NetworkError when attempting to fetch resource.