old_contents: // Time-stamp: "2018-04-14 21:07:05 phil"
  
  dumpln("50os.linux");
  
  content_handlers.set("application/pdf", content_handler_save);
  
  external_content_handlers.set("image/*", "xdg-open");
  external_content_handlers.set("video/*", "xdg-open");
  external_content_handlers.set("audio/*", "xdg-open");
  external_content_handlers.set("application/pdf", "xdg-open");
  external_content_handlers.set("application/postscript", "xdg-open");
  external_content_handlers.set("application/x-dvi", "xdg-open");
  
new_contents: // Time-stamp: "2019-01-27 00:55:30 phil"
  
  dumpln("50os.linux");
  
  content_handlers.set("application/pdf", content_handler_save);
  
  external_content_handlers.set("image/*", "xdg-open");
  external_content_handlers.set("video/*", "yd2tv");
  external_content_handlers.set("audio/*", "yd2tv");
  external_content_handlers.set("application/octet-stream", "yd2tv");
  external_content_handlers.set("application/pdf", "xdg-open");
  external_content_handlers.set("application/postscript", "xdg-open");
  external_content_handlers.set("application/x-dvi", "xdg-open");
  
subject: Set up handlers for shell-command-on-url.