Multiple Qt/KDE integration issues under Cinnamon (Arch-based distributions mostly)

[DocBretti]

Distribution

EndeavourOS Cinnamon

Package version

6.6.8-1

Graphics hardware in use

Radeon RX 7800 XT

Frequency

Always

Bug description

Environment

• EndeavourOS (current)
• Linux Mint 22.3 Cinnamon (same behavior)
• Cinnamon (X11)
• KDE Frameworks 6
• KDE Connect 26.04.2
• Huawei Pura 70 Ultra (EMUI 14.2 / Android 14)

Reference system:

• Debian Sid + Plasma 6
• Same phone
• Same network
• Everything works correctly.

---

Summary

Several independent Qt/KDE applications exhibit problems under Cinnamon while working correctly under Plasma.

The issue appears to affect the integration between Cinnamon and Qt/KIO/xdg-desktop-portal rather than KDE Connect itself.

---

Observed problems

KDE Connect filesystem browsing

The phone pairs successfully.

Connection establishment succeeds.

The SFTP subsystem works.

However, graphical browsing from KDE Connect (and Dolphin) displays an empty directory.

---

Dolphin

Launching Dolphin under Cinnamon prints:

Could not activate remote peer 'org.freedesktop.portal.Desktop'
Failed to register with host portal

---

xdg-desktop-portal

graphical-session.target
Active: inactive (dead)

xdg-desktop-portal.service
Dependency failed

Portal startup fails because graphical-session.target is never activated.

---

Additional affected applications

The following applications also malfunction under Cinnamon but work correctly under Plasma:

• KDE Connect filesystem browser
• Flameshot >= 14
• Forkgram
• Ayugram

This suggests a general Qt/KDE integration issue.

---

Terminal diagnostics

SFTP connection succeeds

sftp -P 1739 ...
Connected to phone

The connection itself is valid.

---

Root directory cannot be listed

sftp> ls
remote readdir("/"): Permission denied

This is expected Android Scoped Storage behavior.

---

Internal storage is accessible

sftp> cd storage/emulated/0
sftp> ls
Android
DCIM
Download
Movies
Music
Pictures
...

The exported filesystem itself works correctly.

---

sshfs mount exists

cat /proc/<pid>/mountinfo

shows

fuse.sshfs
kdeconnect@192.168.x.x:/

indicating that the FUSE mount succeeds.

---

Mountpoint cannot be listed

ls /run/user/.../UUID

returns

Permission denied

despite

drwxr-xr-x

permissions.

---

graphical-session.target

systemctl --user status graphical-session.target

returns

Active: inactive (dead)

during an active Cinnamon session.

---

xdg-desktop-portal

systemctl --user status xdg-desktop-portal.service

returns

Dependency failed

because

Requisite=graphical-session.target

cannot be satisfied.

---

graphical-session.target cannot be started manually

systemctl --user start graphical-session.target

returns

Operation refused
RefuseManualStart=yes

indicating that the desktop session should activate this target automatically, but does not.

---

Portal startup fails repeatedly

systemctl --user restart xdg-desktop-portal.service

always results in

Dependency failed

---

KIO sees KDE Connect devices

kioclient5 ls kdeconnect:/

returns

Meins
HBP-LX9

meaning the KIO slave itself works.

However, opening the device results in an empty directory instead of the phone storage.

---

Comparison

Component | Cinnamon | Plasma -- | -- | -- KDE Connect pairing | OK | OK SSH connection | OK | OK SFTP | OK | OK Manual access to /storage/emulated/0 | OK | OK KDE Connect GUI browser | Broken | OK Dolphin browsing | Broken | OK Flameshot >=14 | Broken | OK Forkgram | Broken | OK Ayugram | Broken | OK xdg-desktop-portal | Broken | OK

---

Expected behavior

Qt/KDE applications should function identically under Cinnamon and Plasma.

The KDE Connect filesystem browser should automatically enter the exported storage directory and display the phone contents.

---

Actual behavior

Under Cinnamon, multiple Qt/KDE applications fail or behave incorrectly while all tested functionality works correctly under Plasma on the same hardware.

The evidence suggests a missing or broken Cinnamon integration with Qt6/KIO/xdg-desktop-portal rather than a KDE Connect transport issue.

Steps to reproduce

Steps to Reproduce
Install EndeavourOS with Cinnamon 6.6.8 (also reproducible on Linux Mint 22.3 Cinnamon).
Install:
KDE Connect 26.04.2
Dolphin
KIO/KIO Extras
xdg-desktop-portal-xapp
Pair an Android device (tested with Huawei Pura 70 Ultra, EMUI 14.2 / Android 14) via KDE Connect.
Enable Filesystem Exposure on the Android device.
Open the device from the KDE Connect applet or from Dolphin (kdeconnect:/).
Expected Result

The internal storage (/storage/emulated/0) should be opened and files should be visible.

Actual Result

The GUI opens an empty directory (or an incorrect root directory), although the phone is connected successfully.

Additional verification

The KDE Connect transport itself appears to work correctly:

sftp -P 1739
-o IdentityFile=$HOME/.config/kdeconnect/privateKey.pem
-o StrictHostKeyChecking=no
-o UserKnownHostsFile=/dev/null
kdeconnect@

Inside the SFTP session:

pwd
/
ls
Permission denied

cd storage/emulated/0
ls
Android
DCIM
Download
Movies
Music
Pictures
...

The exported storage is therefore accessible via SFTP.

The issue only affects the graphical integration (KDE Connect/Dolphin under Cinnamon).

Additional observations

Under the same hardware and network environment:

Debian Sid + Plasma 6: Works correctly.
CachyOS + Plasma 6: Works correctly.
EndeavourOS + Cinnamon 6.6.8: Fails.
Linux Mint 22.3 Cinnamon: Fails with the same symptoms.

This suggests a Cinnamon-specific integration issue rather than a KDE Connect transport problem.

Additional observations

During debugging, it was noticed that graphical-session.target remains inactive throughout the entire Cinnamon session:

systemctl --user status graphical-session.target

Output:

Active: inactive (dead)

As a consequence, xdg-desktop-portal.service cannot be started:

systemctl --user status xdg-desktop-portal.service

Output:

Dependency failed

The service definition contains:

Requisite=graphical-session.target
After=graphical-session.target

which means the inactive graphical-session.target prevents xdg-desktop-portal from starting.

Attempts to start graphical-session.target manually fail as expected:

systemctl --user start graphical-session.target
Operation refused
RefuseManualStart=yes

indicating that the desktop session itself is expected to activate this target automatically, but does not.

Since several unrelated Qt/KDE applications exhibit Cinnamon-specific issues while working flawlessly under Plasma on the same hardware (KDE Connect filesystem browsing, Dolphin, Flameshot ≥14, Forkgram, Ayugram), this inactive graphical-session.target and the resulting portal failure may be the underlying cause of the observed problems rather than individual application bugs.

Expected behavior

Expected behavior

When logging into a Cinnamon desktop session, graphical-session.target should be activated automatically by the session manager.

As a result, xdg-desktop-portal.service should start successfully, allowing Qt/KDE applications to integrate correctly with the desktop environment.

Applications such as Dolphin, KDE Connect, Flameshot, Forkgram and Ayugram should work as expected without portal-related errors or missing functionality.

In particular, the KDE Connect filesystem browser should automatically open the device's exported storage (/storage/emulated/0) and display its contents, matching the behavior observed under Plasma on the same hardware and software versions.

Additional information

No response

[leigh123linux]

Fixed in 6.7.2-unstable e01c8c3

[leigh123linux]

Also a duplicate of linuxmint/cinnamon#13812

[leigh123linux]

Install EndeavourOS with Cinnamon 6.6.8 (also reproducible on Linux Mint 22.3 Cinnamon).

Don't bullshit, the issue doesn't affect linuxmint, they are LTS based.
The blame is on Archlinux for updating xdg-desktop-portal to 1.21.0+, see

flatpak/xdg-desktop-portal@4d284de

[DocBretti]

Possible resolution

According to reports from other users, this issue appears to be fixed in Cinnamon 6.7.2.

The fix seems to be related to changes in xdg-desktop-portal regarding desktop environments that do not activate graphical-session.target automatically.

If confirmed, the observed KDE Connect, Dolphin and Qt application issues were likely secondary effects caused by the missing portal initialization rather than bugs in the applications themselves.

The issue could therefore be considered resolved once Cinnamon integrates the corresponding xdg-desktop-portal changes.

[DocBretti]

Install EndeavourOS with Cinnamon 6.6.8 (also reproducible on Linux Mint 22.3 Cinnamon).

Don't bullshit, the issue doesn't affect linuxmint, they are LTS based. The blame is on Archlinux for updating xdg-desktop-portal to 1.21.0+, see

flatpak/xdg-desktop-portal@4d284de

Tried kdeconnect on Mint 22.3 Live and the issue appeared. At least with kdeconnect.

[leigh123linux]

Install EndeavourOS with Cinnamon 6.6.8 (also reproducible on Linux Mint 22.3 Cinnamon).

Don't bullshit, the issue doesn't affect linuxmint, they are LTS based. The blame is on Archlinux for updating xdg-desktop-portal to 1.21.0+, see
flatpak/xdg-desktop-portal@4d284de

Tried kdeconnect on Mint 22.3 Live and the issue appeared. At least with kdeconnect.

The cause isn't the same, they have old xdg-desktop-portal and ubuntu upstream reverted the xdg-desktop-portal commit.