I can confirm that something is definitely wrong, but it's not clear what or why. Some links work as expected while others don't.

I can reproduce the bug for links that use the same domain as https://invent.kde.org/

I cannot reproduce the bug for links that use the same domain as https://bugs.kde.org/

KMail does not have any problem opening either kind of link, so this could be a Thunderbird bug.

I have the same version of Thunderbird and openSUSE Tumbleweed as the reporter, but I am using git master versions of KDE software built from source no more than a 5 days old.

An additional comment:

Some of the failed links are trying to run the wine browser and failing.

I can't reproduce this issue with Thunderbird 128.2.0esr with everything KDE built from git master as of today.

Can you paste the output of running `grep http ~/.config/mimeapps.list` in a terminal window?

jc@localhost:~$ grep http ~/.config/mimeapps.list
x-scheme-handler/http=org.chromium.Chromium.desktop;firefox.desktop;chromium-browser.desktop;
x-scheme-handler/https=org.chromium.Chromium.desktop;firefox.desktop;chromium-browser.desktop;
x-scheme-handler/http=org.chromium.Chromium.desktop;
x-scheme-handler/https=org.chromium.Chromium.desktop;
jc@localhost:~$

Thanks. Can you reproduce the issue in a new clean user account?

I created a new user on my openSUSE system and attempted to connect to my email account. 

The connection failed sekecting the default IMAP setup.

I was able to show the type of email account that was available but I could not log in from Thunderbird. I was able to log in from Firefox at the same time. 

Stymied!

I connected Thunderbird to my gmail account and it worked!

I tried printing an email and it hung up just as it had with my regular Comcast account.

I created the account, tried to connect to my Comcast account and had the failures described. Then I connected to my gmail account and tried to print. It hung up in the same way previously described.

Other than that, the system was as bare as I can get.
 
To recap.
openSUSE Tumbleweed. Up to date.
KDE up to date.

Printing an email? I thought this bug report was about clicking links in emails, and them not opening in your web browser as expected. Does that work in the new clean user account?

Sorry. I have two problems. Plus you just demonstrated a third.
1. Links don't work consistently.
2. Printing doesn't work.
3. Setting up an empty account doesn't work. 

I'll try the link, too.

Printing and setting up a new account are definitely not KDE issues (Thunderbird isn't a KDE app) so let's focus on the "opening links" issue here.

I definitely agree. 

I am confused by the Thunderbird related bugs and KDE.

This bug reported does not repeat on my "empty" system. 

The error messages I am seeing come from a small dialog in the upper right corner of the screen. They talk about kioexec copying, finished, and errors. I don't see the same message in the bare system.

Thanks, that's helpful. If the issue doesn't happen in a new clean user account, this strongly suggests it's related to a configuration issue on your main user account. Unfortunately I'm not knowledgeable enough about the internals of KIO to know what setting might be causing it.

Could you attach your `~/.config/kdeglobals` file after removing any personal information?

🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!

Thank you for the reminder. Here is my kdeglobals file. I still have the problem.

c@localhost:~$ cat ~/.config/kdeglobals
[$Version]
update_info=filepicker.upd:filepicker-remove-old-previews-entry,fonts_global.upd:Fonts_Global,fonts_global_toolbar.upd:Fonts_Global_Toolbar,icons_remove_effects.upd:IconsRemoveEffects,kwin.upd:animation-speed,style_widgetstyle_default_breeze.upd:StyleWidgetStyleDefaultBreeze

[ColorEffects:Disabled]
ChangeSelectionColor=
Color=56,56,56
ColorAmount=0
ColorEffect=0
ContrastAmount=0.65
ContrastEffect=1
Enable=
IntensityAmount=0.1
IntensityEffect=2

[ColorEffects:Inactive]
ChangeSelectionColor=true
Color=112,111,110
ColorAmount=0.025
ColorEffect=2
ContrastAmount=0.1
ContrastEffect=2
Enable=false
IntensityAmount=0
IntensityEffect=0

[Colors:Button]
BackgroundAlternate=189,195,199
BackgroundNormal=239,240,241
DecorationFocus=61,174,233
DecorationHover=147,206,233
ForegroundActive=61,174,233
ForegroundInactive=127,140,141
ForegroundLink=41,128,185
ForegroundNegative=218,68,83
ForegroundNeutral=198,92,0
ForegroundNormal=35,38,39
ForegroundPositive=39,174,96
ForegroundVisited=127,140,141

[Colors:Complementary]
BackgroundAlternate=59,64,69
BackgroundNormal=49,54,59
DecorationFocus=30,146,255
DecorationHover=61,174,230
ForegroundActive=147,206,233
ForegroundInactive=175,176,179
ForegroundLink=61,174,230
ForegroundNegative=231,76,60
ForegroundNeutral=253,188,75
ForegroundNormal=239,240,241
ForegroundPositive=46,204,113
ForegroundVisited=61,174,230

[Colors:Selection]
BackgroundAlternate=29,153,243
BackgroundNormal=61,174,233
DecorationFocus=61,174,233
DecorationHover=147,206,233
ForegroundActive=252,252,252
ForegroundInactive=239,240,241
ForegroundLink=253,188,75
ForegroundNegative=176,55,69
ForegroundNeutral=246,116,0
ForegroundNormal=252,252,252
ForegroundPositive=23,104,57
ForegroundVisited=189,195,199

[Colors:Tooltip]
BackgroundAlternate=77,77,77
BackgroundNormal=35,38,39
DecorationFocus=61,174,233
DecorationHover=147,206,233
ForegroundActive=61,174,233
ForegroundInactive=189,195,199
ForegroundLink=41,128,185
ForegroundNegative=218,68,83
ForegroundNeutral=246,116,0
ForegroundNormal=252,252,252
ForegroundPositive=39,174,96
ForegroundVisited=127,140,141

[Colors:View]
BackgroundAlternate=239,240,241
BackgroundNormal=252,252,252
DecorationFocus=61,174,233
DecorationHover=147,206,233
ForegroundActive=61,174,233
ForegroundInactive=127,140,141
ForegroundLink=41,128,185
ForegroundNegative=218,68,83
ForegroundNeutral=246,116,0
ForegroundNormal=35,38,39
ForegroundPositive=39,174,96
ForegroundVisited=127,140,141

[Colors:Window]
BackgroundAlternate=189,195,199
BackgroundNormal=239,240,241
DecorationFocus=61,174,233
DecorationHover=147,206,233
ForegroundActive=61,174,233
ForegroundInactive=127,140,141
ForegroundLink=41,128,185
ForegroundNegative=218,68,83
ForegroundNeutral=246,116,0
ForegroundNormal=35,38,39
ForegroundPositive=39,174,96
ForegroundVisited=127,140,141

[DirSelect Dialog]
DirSelectDialog Size=905,584
History Items[$e]=file:$HOME,file:$HOME/devel/TaperFoil/build/Qt_in_PATH_System-Release,file:$HOME/devel,file:$HOME/devel,file:$HOME/devel/TaperFoil,file:///misc/devel/taperfoil/TaperFoil,file:///misc/devel/taperfoil/build-TaperFoil-Desktop-Debug,file:///misc/devel/taperfoil,file:///misc/devel,file:///misc/MP3blues,file:///misc/MP3,file:$HOME/Documents,file:$HOME/Documents,file:$HOME/Documents,file:$HOME/Documents,file:$HOME/Downloads,file:$HOME/Documents,file:$HOME/Documents,file:$HOME/Documents,file:$HOME/Documents,file:$HOME/Documents,file:$HOME/Documents,file:$HOME/Documents,file:$HOME/Pictures-NationalParksAndLodgesTrip,file:$HOME/Pictures2021,file:$HOME/LocalMailFolders,file:$HOME/Mail,file:$HOME/Local_Mail_Folders,file:$HOME//thunderbird,file:$HOME/.thunderbird,file:$HOME/thunderbird

[General]
BrowserApplication=chromium-browser.desktop
ColorSchemeHash=a6aeb2c7d22e33b7dc024f40f0daed0f793a1dac
Name=Breeze Light
shadeSortColumn=true
widgetStyle=Breeze

[KDE]
AnimationDurationFactor=0.25
ColorScheme=BreezeLight
contrast=4
widgetStyle=Breeze

[KFileDialog Settings]
Allow Expansion=false
Automatically select filename extension=false
Breadcrumb Navigation=false
Decoration position=2
LocationCombo Completionmode=5
PathCombo Completionmode=5
Show Bookmarks=false
Show Full Path=false
Show Inline Previews=true
Show Preview=false
Show Speedbar=true
Show hidden files=false
Sort by=Name
Sort directories first=true
Sort hidden files last=false
Sort reversed=false
Speedbar Width=138
View Style=DetailTree

[KScreen]
ScreenScaleFactors=None-1=1;
XwaylandClientsScale=false

[KShortcutsDialog Settings]
Dialog Size=600,480

[WM]
activeBackground=71,80,87
activeBlend=252,252,252
activeForeground=252,252,252
inactiveBackground=239,240,241
inactiveBlend=75,71,67
inactiveForeground=189,195,199
jc@localhost:~$

Looking at the file associations, I noticed that the winebrowser was in the list of possible consumers of an html file. Removing this made my life better. I now seem to be able to follow the link, even though the winebrowser entry isn't on the top of the list.

Oh, well that makes perfect sense. If a rogue app hijacked HTTP links, that would explain it. Please report this to the developers of that app; apps should never do this. Thanks!