Bug 442721

Maybe we're seeing the same thing?

https://bugs.kde.org/show_bug.cgi?id=443319

Can confirm this on kf5 5.86.0.

Hope following snippet is helpful.

Before, below code would open the example.js file in text editor.
Now it fails with:
```
kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found
Could not launch external editor.
```

```
	const QUrl script = QUrl::fromLocalFile("..../scripts/example.js");
	KIO::OpenUrlJob *job = new KIO::OpenUrlJob(script);
	job->setUiDelegate(new KIO::JobUiDelegate(KJobUiDelegate::AutoHandlingEnabled, app()->mainWindow()));
	if(!job->exec()) {
		qDebug() << job->errorString();
		if(!QDesktopServices::openUrl(script))
			qDebug() << "Could not launch external editor.";
	}
```

*** Bug 443319 has been marked as a duplicate of this bug. ***

Looks like it's fixed in 5.87.0

Present with 5.87 for me.

This bug can be triggered by both "xdg-open" and "kde-open5".

I think I just find the related code is here:

It bypasses "x-scheme-handler" but didn't bypass "x-scheme-handler/file",

https://invent.kde.org/frameworks/kservice/-/blob/v5.89.0/src/services/kapplicationtrader.cpp#L26

The last comment is wrong, but I cannot edit it. The code was submitted here.

https://phabricator.kde.org/D25698

I'm encountering this issue on kf5 5.90.0:

    $ xdg-open .
    kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found

KDE Plasma Version: 5.23.5
KDE Frameworks Version: 5.90.0
Qt Version: 5.15.2
Graphics Platform: Wayland

I'm encountering this on an up-to-date Arch Linux system.

Plasma Desktop: 5.24.2
KDE Frameworks: 5.91.0
Qt: 5.15.2
Platform: X11
Hardware: Nvidia

The bug can be reproduced consistently on my multi-monitor setup:

1. Open "Display Configuration" in System Settings
2. Disable primary monitor
3. Enable primary monitor after some time

The above steps are sufficient to reproduce the problem. Restarting kwin/plasmadesktop does not help. The problem does not occur on a fresh restart though. The monitor needs to be disabled to reproduce it.

Examining with Journalctl, I see :


kwin_x11[2736]: qt.qpa.xcb: QXcbConnection: XCB error: 3 (BadWindow), sequence: 16715, resource id: 138412039, major code: 18 (ChangeProperty), minor code: 0
kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found
kioclient5[196052]: kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found
kwin_x11[2736]: qt.qpa.xcb: QXcbConnection: XCB error: 3 (BadWindow), sequence: 8651, resource id: 142606341, major code: 18 (ChangeProperty), minor code: 0
kwin_x11[2736]: qt.qpa.xcb: QXcbConnection: XCB error: 3 (BadWindow), sequence: 8656, resource id: 142606342, major code: 18 (ChangeProperty), minor code: 0
kwin_x11[2736]: qt.qpa.xcb: QXcbConnection: XCB error: 3 (BadWindow), sequence: 8660, resource id: 142606343, major code: 18 (ChangeProperty), minor code: 0

a workaround has been found - you need to:

enable hidden files in dolphin then go to your home dir (/home/username) then go to hidden .config dir in there you need to find file named mimeapps.list edit it,  add this string (x-scheme-handler/file=org.kde.dolphin.desktop;) to all sub strings for example:

[Added Associations]
.....
.....
x-scheme-handler/file=org.kde.dolphin.desktop;

[Default Applications]
.....
.....
x-scheme-handler/file=org.kde.dolphin.desktop;

then execute this command in the terminal:  update-mime-database ~/.local/share/mime

it's worked for me, after that system links has became open in dolphin

more info:
https://wiki.archlinux.org/title/XDG_MIME_Applications
https://bugzilla.redhat.com/show_bug.cgi?id=674321

(In reply to pridoorok from comment #10)
> a workaround has been found - you need to:

Wow! That worked perfectly! Thank you so much. :)

I wonder why this is even needed for KDE? Why doesn't it "just work" as expected by default?

(In reply to pridoorok from comment #10)
> a workaround has been found - you need to:
> 
> (x-scheme-handler/file=org.kde.dolphin.desktop;) to all sub strings for

This work around gets rid of the warning for me; but it also unnecessary opens dolphin when I do
`xdg-open /some/file.pdf`.

I'm on Wayland, Frameworks 5.91, Plasma 5.24.4, Fedora 35.

I get the following message when I open any PDF file in Okular 22.04.1 (KDE 5.24.5) via Konsole.

    kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found
    kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found
    qt.xkb.compose: failed to create compose table

https://invent.kde.org/frameworks/kio/-/merge_requests/867

Git commit a4c404603bbf43fda2d60c82c814527bde0a8352 by Ahmad Samir.
Committed on 19/08/2022 at 14:31.
Pushed by ahmadsamir into branch 'master'.

DesktopExecParser: don't kioexec if there is a handler for scheme

This fixes an issue where the code called
KApplicationTrader::queryByMimeType("x-scheme-handler/file"), which would
trigger a warning in KApplicationTrader, because there is no
x-scheme-handler/file mimtype.
FIXED-IN: 5.96

M  +24   -12   src/core/desktopexecparser.cpp

https://invent.kde.org/frameworks/kio/commit/a4c404603bbf43fda2d60c82c814527bde0a8352

I'm seeing this problem again when trying to open directory from Qt application using QDesktopServices::openUrl. It should invoke dolphin to open directory but instead prints:
kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found

Operating System: Fedora Linux 36
KDE Plasma Version: 5.26.0
KDE Frameworks Version: 5.99.0
Qt Version: 5.15.6
Kernel Version: 6.0.5-200.fc36.x86_64 (64-bit)
Graphics Platform: X11

I encounter this bug when using `texdoc` of TeXLive, like this:
```
[firestar @ ArchLinux ~] (08:42:14)
$ texdoc tex
[firestar @ ArchLinux ~] (08:42:16)
$ kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found
```
Then I changed the settings like https://bugs.kde.org/show_bug.cgi?id=442721#c10, I use Okular which is my default app for PDF

But this lead to that other files which do not use Okular will open by Okular now, like jupyter-lab which also use `xdg-open`

I see this issue again when attaching an Android device and launching the file manager:
Mär 10 12:35:18 X1E kernel: usb 1-1: new high-speed USB device number 17 using xhci_hcd
Mär 10 12:35:19 X1E kernel: usb 1-1: New USB device found, idVendor=04e8, idProduct=6860, bcdDevice= c.00
Mär 10 12:35:19 X1E kernel: usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Mär 10 12:35:19 X1E kernel: usb 1-1: Product: SAMSUNG_Android
Mär 10 12:35:19 X1E kernel: usb 1-1: Manufacturer: SAMSUNG
Mär 10 12:35:19 X1E kernel: usb 1-1: SerialNumber: RF8M72D9FLZ
Mär 10 12:35:19 X1E kernel: cdc_acm 1-1:1.1: ttyACM0: USB ACM device
Mär 10 12:35:19 X1E kernel: usbcore: registered new interface driver cdc_acm
Mär 10 12:35:19 X1E kernel: cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters

Mär 10 12:35:24 X1E plasmashell[2149]: DeviceServiceAction::execute:  "/org/kde/solid/udev/sys/devices/pci0000:00/0000:00:14.0/usb1/1-1"  is not a StorageAccess device
Mär 10 12:35:24 X1E systemd[1867]: Started Dolphin - Dateiverwaltung.
Mär 10 12:35:24 X1E kde-open5[6597]: kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found
Mär 10 12:35:24 X1E akonadiserver[2562]: org.kde.pim.akonadiserver: ItemRetrievalJob for request 62421 finished
Mär 10 12:35:24 X1E systemd[1867]: Started Dolphin - Dateiverwaltung.

-> Dolphin opens the home directory instead
Operating System: openSUSE Tumbleweed 20230306
KDE Plasma Version: 5.27.2
KDE Frameworks Version: 5.103.0
Qt Version: 5.15.8
Kernel Version: 6.2.1-1-default (64-bit)

I see this in terminal just after "xdg-open ~" command. KDE 5.27.3

I still have this problem on KDE-Framework-Version: 5.108.0 while using Qt programs on xwayland that try to open documents with QDesktopServices::openUrl()

I found out that this mimetype handling problem only arise if I try to use my own Qt libs v5.15.2 
Same libs working fine on GTK (XFCE). No idea why they fail on KDE?

This is still an issue on KDE Frameworks 5.110.0. Trying to run `~/.fightcade2/Fightcade.sh roms` gives:

kf.service.services: KApplicationTrader: mimeType "x-scheme-handler/file" not found

Getting this for all my .desktop files when running them through kioclient exec or xdg-open, though none of them are failing to launch because of it. The said kf.service.services warning also only shows in terminal output, I never see it in my journal unlike the logs for other plasmashell kf.service components.

X11, Framework 5.111.0, KDE 5.27.9, Qt 5.15.11, Manjaro

Git commit d0f416ea064539adbffb471d7e0d9767c7d125a9 by David Faure.
Committed on 03/03/2024 at 09:27.
Pushed by dfaure into branch 'kf5'.

Fix warning: mimeType "x-scheme-handler/file" not found

commit b5af9b4eb021f772ce27b466409f6bd1efd72969 ported KIO::DesktopExecParser::hasSchemeHandler
from KMimeTypeTrader to KApplicationTrader, but it turns out there was a slight difference
between the two: KMimeTypeTrader had two if()s for silencing the x-scheme-handler/* warnings,
while KApplicationTrader had only one. Maybe I misread the code back then and failed to see
the "mime = mimeType" line (rather than return) which makes us proceed further down after
QMimeDatabase says the mimetype doesn't exist.
FIXED-IN: 5.116

M  +3    -1    src/services/kapplicationtrader.cpp

https://invent.kde.org/frameworks/kservice/-/commit/d0f416ea064539adbffb471d7e0d9767c7d125a9

Git commit 3e5a56b9a38258e81362261df9d9288ebfb13eaa by David Faure.
Committed on 03/03/2024 at 09:28.
Pushed by dfaure into branch 'master'.

Fix warning: mimeType "x-scheme-handler/file" not found

commit b5af9b4eb021f772ce27b466409f6bd1efd72969 ported KIO::DesktopExecParser::hasSchemeHandler
from KMimeTypeTrader to KApplicationTrader, but it turns out there was a slight difference
between the two: KMimeTypeTrader had two if()s for silencing the x-scheme-handler/* warnings,
while KApplicationTrader had only one. Maybe I misread the code back then and failed to see
the "mime = mimeType" line (rather than return) which makes us proceed further down after
QMimeDatabase says the mimetype doesn't exist.
FIXED-IN: 5.116
(cherry picked from commit d0f416ea064539adbffb471d7e0d9767c7d125a9)

M  +3    -1    src/services/kapplicationtrader.cpp

https://invent.kde.org/frameworks/kservice/-/commit/3e5a56b9a38258e81362261df9d9288ebfb13eaa

*** Bug 481263 has been marked as a duplicate of this bug. ***