Paul I thank you that you had take a look at this old bug report.
Currently, having 2 Ubuntu machines (one on 16.04 and another on 18.04), I never had this issue anymore. It seems to be fixed. Best regards Philippe -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to thunderbird in Ubuntu. https://bugs.launchpad.net/bugs/879431 Title: Thunderbird opens firefox default page when clicking a link Status in thunderbird package in Ubuntu: Incomplete Bug description: When I click a link in received e-mail, thunderbird just open a new firefox window, witch displays the default page. When I run firefox from a shell, f.ex: firefox www.ubuntu.com , all works ok (if firefox is allready open, a new tab is open an the request page is displayed). I removed the firefox and thunderbird directories ( ~/.thunderbird and ~/.mozilla) : same problem. Release: Ubuntu 11.10 Thunderbird: 7.0.1+build1+nobinonly-0ubuntu1 The system was installed with alternate CD (i386) ProblemType: Bug DistroRelease: Ubuntu 11.10 Package: thunderbird 7.0.1+build1+nobinonly-0ubuntu1 ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4 Uname: Linux 3.0.0-12-generic i686 NonfreeKernelModules: nvidia AddonCompatCheckDisabled: False AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24. ApportVersion: 1.23-0ubuntu3 Architecture: i386 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: philippe 2329 F.... pulseaudio /dev/snd/controlC1: philippe 2329 F.... pulseaudio BuildID: 20110929181644 CRDA: Error: [Errno 2] Aucun fichier ou dossier de ce type Card0.Amixer.info: Card hw:0 'V8237'/'VIA 8237 with ALC655 at 0xc000, irq 22' Mixer name : 'Realtek ALC655 rev 0' Components : 'AC97a:414c4760' Controls : 48 Simple ctrls : 29 Card1.Amixer.info: Card hw:1 'U0x46d0x991'/'USB Device 0x46d:0x991 at usb-0000:00:10.4-8, high speed' Mixer name : 'USB Mixer' Components : 'USB046d:0991' Controls : 2 Simple ctrls : 1 Card1.Amixer.values: Simple mixer control 'Mic',0 Capabilities: cvolume cvolume-joined cswitch cswitch-joined penum Capture channels: Mono Limits: Capture 0 - 3072 Mono: Capture 1536 [50%] [24.00dB] [on] Channel: release Date: Fri Oct 21 14:43:11 2011 EcryptfsInUse: Yes ForcedLayersAccel: False InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release i386 (20111011) IpRoute: default via 192.168.1.2 dev eth0 proto static 169.254.0.0/16 dev eth0 scope link metric 1000 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.101 metric 1 IwConfig: lo no wireless extensions. eth0 no wireless extensions. Prefs: extensions.lastAppVersion - 7.0.1 network.cookie.prefsMigrated - true ProcEnviron: LANGUAGE=fr_CH:fr PATH=(custom, user) LANG=fr_CH.UTF-8 SHELL=/bin/bash Profiles: Profile0 (Default) - LastVersion=7.0.1/20110929181644 (Running) RfKill: RunningIncompatibleAddons: False SourcePackage: thunderbird UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 04/02/01 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: Version 07.00T dmi.board.name: MS-6702 dmi.board.vendor: MSI dmi.board.version: 1.0 dmi.chassis.asset.tag: 0123ABC dmi.chassis.type: 3 dmi.chassis.vendor: Uknown Chassis Manufacture dmi.chassis.version: Version 1.00 dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrVersion07.00T:bd04/02/01:svnMSI:pnMS-6702:pvr1.0:rvnMSI:rnMS-6702:rvr1.0:cvnUknownChassisManufacture:ct3:cvrVersion1.00: dmi.product.name: MS-6702 dmi.product.version: 1.0 dmi.sys.vendor: MSI To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/thunderbird/+bug/879431/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp