SUMMARY I have Brother's HL-5250DN. The default setting for duplex printing in CUPS configuration (http://localhost:631/admin/#General) is None. This should be overridden by the application like Okular for a particular document I want to print. However, when I print PDF document from Okular, duplex setting is ignored. STEPS TO REPRODUCE 1. Open PDF document with Okular 2. Ctrl + P 3. Click "Options >>" button 4. Click "Options" tab 5. Select Long side 6. Click Print OBSERVED RESULT Pages are being printed in separated sheets of paper. EXPECTED RESULT 2 pages should be printed on the same sheet of paper. SOFTWARE/OS VERSIONS Linux/KDE Plasma: linux 5.5.7-arch1-1 / not using plasma Qt Version: 5.14.1 cups 2.3.1-1 brother-cups-wrapper-common 1.0.0 brother-cups-wrapper-laser 2.0.1_2_0ubuntu7-2 ADDITIONAL INFORMATION It is most likely not a problem with QPrintDialog but with Okular. To confirm this you can use any other program that is using QPrintDialog. For example: 1. Install qpdfview 2. Execute section STEPS TO REPRODUCE using qpdfview Results: the duplex setting is working fine.
For further analysis, can you please attach: 1) the PPD of the printer, located at /etc/cups/ppd/<PRINTERNAME>.ppd 2) a CUPS debug log of one such printout (set 'LogLevel debug' in /etc/cups/cupsd.conf, then restart CUPS, print, and attach /var/log/cups/error_log (or the relevant part of it). (Depending on the setting for 'ErrorLog' in /etc/cups/cups-files.conf, the log output may alternatively go to the journal, so either retrieve it from there or set 'ErrorLog /var/log/cups/error_log').
Created attachment 127752 [details] PPD
Cannot reproduce the problem anymore with QT 5.14.2.