Print dialog hangs when PPD file in /etc/cups/ppd/ is not world-readable

It seems that the print dialog of the Chromium browser (the browser's own one with the preview) tries to read the PPD file (the file containing the printer's properties and the printer-specific user-settable options) in /etc/cups/ppd/ directly to be able to display the dialog with correct options and correct preview. The correct method (which is also actually used by the GTK print dialog) is to use the API of the CUPS library or IPP requests to the CUPS daemon.

As it depends on the configuration of CUPS whether the PPD files in /etc/cups/ppd/ are world-readable and so readable for desktop apps run by ordinary users, it easily happens that the direct reading does not work. Therefore it is very important that print dialogs are properly done.

What I am observing currently is that if the PPD of the selected printer is not world-readable the print dialog hangs and is not able to display the preview and the options. The user can only click the link to use the standard GTK dialog.

See also

https://www.cups.org/str.php?L4703

about the world-readability of PPD files.