Bug 423313

Summary: Can not choose different file manager
Product: [Applications] systemsettings Reporter: Alexander Lohnau <alexander.lohnau>
Component: kcm_componentchooserAssignee: Plasma Bugs List <plasma-bugs>
Status: RESOLVED FIXED    
Severity: normal CC: meven.car, nate
Priority: NOR    
Version: unspecified   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: https://invent.kde.org/plasma/plasma-desktop/commit/6fa8a6b1b4ec9cc1125e1bc96f51586e0a1c87ab Version Fixed In: 5.19.3
Sentry Crash Report:

Description Alexander Lohnau 2020-06-21 09:52:41 UTC 
SUMMARY
I played around with the default applications when fixing another bug and noticed that choosing the Nautilus file manager as the default one doesn't get persisted. 

But if you select it under "Other..." it works fine.

KDE Plasma Version: master
KDE Frameworks Version: master
Qt Version: 5.14.2
Comment 1 Nate Graham 2020-06-22 18:04:39 UTC 
Can confirm.
Comment 2 Alexander Lohnau 2020-06-22 18:12:47 UTC 
This seems to be an issue specifically with the natuilus desktop file. It works with Kusader.

When debugging this I noticed that the proposed nautilus entry (called "Files") has the filename org.gnome.Nautilus.desktop.
But looking at this file we see:
>OnlyShowIn=Unity;GNOME;

But when adding the enty manualls the nautilus.desktop file is used. There we see:
>NotShowIn=Unity;GNOME;

So it looks like KServiceTypeTrader returns the "wrong" desktop file.
Comment 3 Méven Car 2020-06-23 08:58:02 UTC 
As Alexander noticed nautilus has two .desktop files, one for when in GNOME and the other one elsewhere using the `OnlyShowIn` filter.

The KCM ignores the `OnlyShowIn` here on purpose to be able to select any installed File manager, but perhaps should not. And once we select it KServiceTrader ignores such a selected application with "OnlyShowIn!=KDE".

The issue in fact first arises with `nautilus.desktop` file that has no Mimetype field at all, and the KCM uses `MimeType=inode/directory` to find file managers.

So the issue could be that we should exclude `OnlyShowIn!=KDE` and the other one that we should relax the `MimeType=inode/directory` expectations, alternatively accepting `Category=FileManager`.
Comment 4 Méven Car 2020-06-24 07:16:12 UTC 
Git commit 6fa8a6b1b4ec9cc1125e1bc96f51586e0a1c87ab by Méven Car.
Committed on 23/06/2020 at 10:25.
Pushed by meven into branch 'Plasma/5.19'.

KCM component chooser: use the category FileManager to filter filemanager apps
FIXED-IN: 5.19.2

M  +7    -3    kcms/componentchooser/componentchooserfilemanager.cpp

https://invent.kde.org/plasma/plasma-desktop/commit/6fa8a6b1b4ec9cc1125e1bc96f51586e0a1c87ab