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Application missing from "Applications" dialog, so how can I set it to "Always Ask"?

  • 5 பதிலளிப்புகள்
  • 2 இந்த பிரச்னைகள் உள்ளது
  • 10 views
  • Last reply by cor-el

When I download some file types, such as CSV or JSON, they automatically open in LibreOffice.

I want to use a different program for JSON files.

However, when I navigate to the "Applications" settings dialog, none of these file types are listed. There is no entry for CSV, nor for JSON, nor are there any mentions of LibreOffice whatsoever.

This dialog does not let me add new file types, so I am at a loss as to how to change this behavior.

Are these settings hidden away somewhere in my profile directory, perhaps? Can I edit them there?

Note: The same occurs if I click on the downloaded file from the "Downloads" list.

When I download some file types, such as CSV or JSON, they automatically open in LibreOffice. I want to use a different program for JSON files. However, when I navigate to the "Applications" settings dialog, none of these file types are listed. There is no entry for CSV, nor for JSON, nor are there any mentions of LibreOffice whatsoever. This dialog does not let me add new file types, so I am at a loss as to how to change this behavior. Are these settings hidden away somewhere in my profile directory, perhaps? Can I edit them there? Note: The same occurs if I click on the downloaded file from the "Downloads" list.

All Replies (5)

Note: I suppose this might be related to this 3-year-old-but-not-fixed bug: https://bugzilla.mozilla.org/show_bug.cgi?id=727422

Go to the "Applications" page, and use its search bar.

The file action usually depends on with what content-type the server sends the file.

You can use the Live Http Headers extension to check the content type.

If the server sends the file as a generic type like "application/octet-stream" then you can't set an action, but that wouldn't happen if a specific application is chosen.

You can check the mimeTypes.rdf file in the Firefox profile folder for a reference to the file extension.

You can use this button to go to the current Firefox profile folder:

cor-el said

The file action usually depends on with what content-type the server sends the file.

It is true that the server is giving a bogus content type.

However, that can't be the full issue, since I have the same problem when clicking the downloaded file in the "Downloads" listing.

Further, different applications are launched for the .json vs .csv file, so FireFox is clearly somehow distinguishing them (Writer is opened for one, Calc for the other).

You can check the mimeTypes.rdf file in the Firefox profile folder for a reference to the file extension.

There is no mention of libreoffice in here whatsoever.

This is on Linux, and it seems like application selection is a bit messy there (see the bug I referenced), so i'm not 100% sure where that info is coming from.

Possibly /usr/share/applications/mimeinfo.cache, which it really should not be using (again, see bug).

Bleh, this is a bit of a rabbit hole (:

You can use a command like this in a terminal window to check (query) the default application and set the default application.

  • MIME type:
    xdg-mime query default application/pdf
  • File extension:
    xdg-mime query filetype *.pdf
  • Set default application for a MIME type:
    xdg-mime default evince-2.desktop application/pdf