Frequent popup asking for Gmail Calendar password

[John Rose]

I'm frequently being prompted by a popup (initiated by Thunderbird?) to input my password for Google Calendar, even though I've removed my Gmail account (with its data) from ThunderBird though I haven't deleted the Gmail a/c as I use that a/c for my Android phone's Gmail a/c : interestingly, the popup then asks again presumably due to rejecting my correct password! Any ideas on how to stop this popup appearing or to get the password accepted by the popup?
PS Ubuntu 20.04 & Thunderbird 91.7.0

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: thunderbird 1:91.7.0+build2-0ubuntu0.20.04.1
ProcVersionSignature: Ubuntu 5.4.0-107.121-generic 5.4.174
Uname: Linux 5.4.0-107-generic x86_64
AddonCompatCheckDisabled: False
ApportVersion: 2.20.11-0ubuntu27.21
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: john 79628 F.... pulseaudio
BuildID: 20220305171341
CasperMD5CheckResult: skip
Channel: Unavailable
CurrentDesktop: ubuntu:GNOME
Date: Wed Apr 13 08:24:44 2022
Extensions: extensions.sqlite corrupt or missing
ForcedLayersAccel: False
IfupdownConfig:
 # interfaces(5) file used by ifup(8) and ifdown(8)
 auto lo
 iface lo inet loopback
IncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite)
InstallationDate: Installed on 2016-07-25 (2087 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
IpRoute:
 default via 192.168.0.1 dev wlan0 proto dhcp metric 600
 169.254.0.0/16 dev wlan0 scope link metric 1000
 192.168.0.0/24 dev wlan0 proto kernel scope link src 192.168.0.12 metric 600
Locales: extensions.sqlite corrupt or missing
MostRecentCrashID: bp-28b95fb0-9b5b-48f3-8c3d-5c4b52161212
PrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/thunderbird/omni.ja:greprefs.js:359
PrefSources: prefs.js
Profiles: Profile0 (Default) - LastVersion=91.7.0/20220305171341 (In use)
RunningIncompatibleAddons: False
SourcePackage: thunderbird
SubmittedCrashIDs: bp-28b95fb0-9b5b-48f3-8c3d-5c4b52161212
Themes: extensions.sqlite corrupt or missing
UpgradeStatus: Upgraded to focal on 2020-09-30 (559 days ago)
dmi.bios.date: 01/12/2016
dmi.bios.vendor: LENOVO
dmi.bios.version: CCCN19WW(V2.05)
dmi.board.asset.tag: NO Asset Tag
dmi.board.name: Lenovo B50-10
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40700 WIN
dmi.chassis.asset.tag: NO Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Lenovo B50-10
dmi.modalias: dmi:bvnLENOVO:bvrCCCN19WW(V2.05):bd01/12/2016:svnLENOVO:pn80QR:pvrLenovoB50-10:rvnLENOVO:rnLenovoB50-10:rvrSDK0J40700WIN:cvnLENOVO:ct10:cvrLenovoB50-10:
dmi.product.family: IDEAPAD
dmi.product.name: 80QR
dmi.product.sku: LENOVO_MT_80QR_BU_idea_FM_Lenovo B50-10
dmi.product.version: Lenovo B50-10
dmi.sys.vendor: LENOVO