This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

xdg-open not being invoked with custom url schema on Linux for Firefox 55 (working on 53 and previous perfectly, on windows also works)

  • 3 balasan
  • 3 ada masalah ini
  • 7 paparan
  • Balasan terakhir oleh agomez

more options

Hi, i'm having a problem with Firefox 55, that was working perfectly on firefox 53 on Linux. This problem does not reproduces on Windows, i mean, on windows custom url schemas are working correctly with Firefox 55. The problem is as follow, We have this .desktop registered application: cat /usr/share/applications/UDSClient.desktop [Desktop Entry] Name=UDSClient Comment=UDS Helper Keywords=uds;client;vdi; Exec=/usr/lib/UDSClient/UDSClient.py %u Icon=help-browser StartupNotify=true Terminal=false Type=Application Categories=Utility; MimeType=x-scheme-handler/uds;x-scheme-handler/udss;

As you can see, this registers an schema handler on Linux Platform. On Firefox 53 this was working correctly, on google chrome, chromium, etc... works fine. In Windows, the registered protocol handler (in the windows register, not using the .desktop file) works, xdg-open with this kind of schema works but with firefox 55 this has stopped working. We only get that the protocol is not recognized and that we should probably install a program that recognizes it.

Thanks for your help,

Adolfo Gómez

Hi, i'm having a problem with Firefox 55, that was working perfectly on firefox 53 on Linux. This problem does not reproduces on Windows, i mean, on windows custom url schemas are working correctly with Firefox 55. The problem is as follow, We have this .desktop registered application: cat /usr/share/applications/UDSClient.desktop [Desktop Entry] Name=UDSClient Comment=UDS Helper Keywords=uds;client;vdi; Exec=/usr/lib/UDSClient/UDSClient.py %u Icon=help-browser StartupNotify=true Terminal=false Type=Application Categories=Utility; MimeType=x-scheme-handler/uds;x-scheme-handler/udss; As you can see, this registers an schema handler on Linux Platform. On Firefox 53 this was working correctly, on google chrome, chromium, etc... works fine. In Windows, the registered protocol handler (in the windows register, not using the .desktop file) works, xdg-open with this kind of schema works but with firefox 55 this has stopped working. We only get that the protocol is not recognized and that we should probably install a program that recognizes it. Thanks for your help, Adolfo Gómez

Diubah oleh agomez

All Replies (3)

more options

Can someone help with this problem please?

more options

Did you try to register this protocol?

Does it give the correct application if you query this MIME type?

  • xdg-mime query default <mime_type>
more options

Hi, thanks for your response. About your question, the response is yes, xdg-mime query returns the correct values. You can take a look here: xdge-mime results

With Firefox 54, we got this as expected: Expected result

I Have also tried the "Registration" method you told me to try, but same result.

When upgraded to firefox 56.0, as can be seen here: Image of firefox version

And them we get this: Image of failed


All of this is very strange, because we have been reported that it is working on some platforms (For example Fedora 26+KDE+Firefox 56.0), but on others (for example, Ubuntu 16.04LTS+gnome-flashback-metacity+Firefox 56.0, clean installation).

The scheme handler is working correctly on Chrome, Chromiun, etc... And i have it running correctly on an Ubuntu with Firefox 56 also!!!.

Also, if we downgrade Firefox, all works fine, if we upgrade it, it fails again.

If you can give us some advice for further investigation. We are a bit lost, because this should work :(

As i told previously, the registered handler was working perfectly (for 5 years at least), and continues working perfectly until Firefox 55, and again, if firefox is downgraded, all works fine :(

Again, thanks for your interest & response,