Thunderbird opens with several error messages

[tomdean]

[calBackendLoader] Using Thunderbird's libical backend
console.debug: "Successfully loaded OpenPGP library librnp.so from /usr/lib/thunderbird/librnp.so"
console.warn: "[l10nregistry] Attempting to synchronously load file\n resource:///chrome/en-US/locale/en-US/calendar/messenger/openpgp/msgReadStatus.ftl while it's being loaded asynchronously."
JavaScript error: resource://gre/modules/ActorManagerChild.jsm, line 297: TypeError: singletons is null
JavaScript error: resource://gre/modules/ActorManagerChild.jsm, line 297: TypeError: singletons is null
JavaScript error: resource://gre/modules/ActorManagerChild.jsm, line 297: TypeError: singletons is null
console.log: (new Error("Cannot load required OTR library", "resource:///modules/OTRLib.jsm", 75))
Extension error: Error while loading 'jar:file:///<email address hidden>!/manifest.json' (NS_ERROR_FILE_NOT_FOUND) resource://gre/modules/Extension.jsm:570 :: readJSON/</<@resource://gre/modules/Extension.jsm:570:20
onStopRequest@resource://gre/modules/NetUtil.jsm:128:18

Extension error: Error while loading 'jar:file:///usr/lib/thunderbird/omni.ja!/chrome/messenger/search-extensions/twitter/manifest.json' (NS_ERROR_FILE_NOT_FOUND) resource://gre/modules/Extension.jsm:570 :: readJSON/</<@resource://gre/modules/Extension.jsm:570:20
onStopRequest@resource://gre/modules/NetUtil.jsm:128:18

console.debug: "public keys: 0, secret keys: 0"
console.debug: "Successfully loaded optional OpenPGP library libgpgme.so.11 from system's standard library locations"
console.debug: "gpgme version: 1.13.1-unknown"

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: thunderbird 1:78.7.1+build1-0ubuntu0.20.04.1
ProcVersionSignature: Ubuntu 5.4.0-72.80-generic 5.4.101
Uname: Linux 5.4.0-72-generic x86_64
AddonCompatCheckDisabled: False
ApportVersion: 2.20.11-0ubuntu27.16
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC2: tomdean 1498 F.... pulseaudio
 /dev/snd/controlC0: tomdean 1498 F.... pulseaudio
 /dev/snd/controlC1: tomdean 1498 F.... pulseaudio
BuildID: 20210203182138
CasperMD5CheckResult: skip
Channel: Unavailable
Date: Thu Apr 15 22:43:09 2021
ForcedLayersAccel: False
IfupdownConfig:
 # interfaces(5) file used by ifup(8) and ifdown(8)
 auto lo
 iface lo inet loopback
IncompatibleExtensions:
 English (GB) Language Pack - <email address hidden>
 Thunderbird (default) - {972ce4c6-7e08-4474-a285-3208198ce6fd}
InstallationDate: Installed on 2019-08-25 (599 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
IpRoute:
 default via 192.168.1.1 dev eno1 proto dhcp metric 100
 169.254.0.0/16 dev eno1 scope link metric 1000
 192.168.1.0/24 dev eno1 proto kernel scope link src 192.168.1.175 metric 100
PrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/thunderbird/omni.ja:greprefs.js:732
PrefSources:
 prefs.js
 user.js
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
Profiles: Profile0 (Default) - LastVersion=78.7.1/20210203182138 (In use)
RunningIncompatibleAddons: True
SourcePackage: thunderbird
UpgradeStatus: Upgraded to focal on 2020-07-20 (269 days ago)
dmi.bios.date: 07/25/2014
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 4801
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: P9X79 PRO
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev 1.xx
dmi.chassis.asset.tag: Asset-1234567890
dmi.chassis.type: 3
dmi.chassis.vendor: Chassis Manufacture
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr4801:bd07/25/2014:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKCOMPUTERINC.:rnP9X79PRO:rvrRev1.xx:cvnChassisManufacture:ct3:cvrChassisVersion:
dmi.product.family: To be filled by O.E.M.
dmi.product.name: System Product Name
dmi.product.sku: SKU
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.