Calibre always opens the PDF file in FileManager instead of default application

Help
,
1

When I click on PDF from Calibre’s main window or click on View it opens up my Dolphin file-manager and shows the following dialog on top of the folder:

Trying to open a file as a folder:'file:///home/shuvashish76/Calibre/Main/Author_name/Book_title.pdf'

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from there (file-manager) if I click on the PDF it opens up my default Okular application.
I’ve already set “File Association” for PDF to open in Okular + Okular as default “PDF viewer” application from system settings.

[If I use Calibre’s “Open with” external-plugin then it does work, so I guess something is misconfiguration on my side. Is it somewhat related file:// URI here?]

How to fix it so that it’ll always open in my default application with Calibre’s View option?

  • Calibre: v9.14 (isolated installation as instructed at official documentation)
  • OS: EndeavourOS x86_64
  • Kernel: Linux 6.18.48-1-lts
  • DE: KDE Plasma 6.7.4
  • WM: KWin (Wayland)
  • Dolphin: v26.08.0
  • KDE Frameworks: 6.29.0 | Qt: Using 6.11.2 and built against 6.11.1

I asked about this at Calibre’s forum and according to the developer it’s something related to xdg-open.

2

What happens when you try to open the file with xdg-open from command line / terminal ?

3

like xdg-open 'filepath.pdf' ? It just opens up the Dolphin with the same message as shown in my OP screenshot, from there clicking “Open as file” works as expected in Okular.

4

Please check in file associations (“kcmshell6 kcm_filetypes” or system settings) if Okular is at the top of the list (see 3 at the pic below)

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5

Did you try :

  • Right clic mouse on the pdf (in Calibre)
  • Select ‘View’ and ‘View with the Calibre eBook Viewer’

It works for me.

6

I’ve already set “File Association” for PDF to open in Okular + Okular as default “PDF viewer” application from system settings. It does open in default app Okular when I click on PDF from Dolphin but not from Calibre. Doesn’t help :frowning:

If you Calibre’s “Preference > Use internal viewer for > PDF” then it’ll open directly in Calibre Viewer when you simply click on Calibre’s “Cover Browser”.

But I’ve disabled that as I don’t want to use Calibre’s Viewer.
When disabled it used to open in whatever app set for default “File Association”, but not anymore so I guess it’s something related to recent QT or xdg-open changes.

Also as I mentioned in Calibre’s forum, it works as expected if I switch to Niri WM that confirms it’s related to QT/xdg-open.

7

xdg-open is a shell script. It tries to find which desktop you use and then decides which tool to use to display the file.

Please check the output of env | egrep "(KDE|XDG)_" if XDG_CURRRENT_DESKTOP and KDE_SESSION_VERSION is set properly.

Please also check kfmclient exec pathAndFileName.pdf .

8 
XDG_CURRENT_DESKTOP=KDE
KDE_SESSION_VERSION=6

bash: kfmclient: command not found

Hmm, do I need some extra package? kfmclient package not available on Arch repo.

9

In this case xdg-open select kde-open to handle the opening. You can also try to call kde-open file.pdf.

Does it make a difference if you call xdg-open with file as parameter or url:

  • xdg-open ~/Documents/file.pdf
  • xdg-open file:///home/user/Documents/file.pdf

(you can try it with kde-open as well)

No. It is the tool xdg-open falls back, when the env variables (see above) are not set. It’s a old tool from the time Konqueror was the default file manager in KDE.

Please try also xdg-mime query default x-scheme-handler/file

When I set this mime-type to org.kde.dolphin.desktop, xdg-open opens both - Dolphin and Okular :astonished_face: