Another standard feature missing in Opera is support for controlling what's printed in the header and footer.
Via "print -> page setup", Firefox and IE have drop-downs so you can specify what goes in the header and footer. For example, you can choose "title", "url", "page number", "page number out of total pages", "date" and "time" etc. You can even choose "empty" so nothing gets printed out for that drop-down. They even allow you to create custom entries in the drop-down.
Any program that prints should have options to configure the headers and footers.
Opera (on windows at least, Mac at least seems to have some of these options) doesn't have any of that. All you have is a checkbox for turning printing of headers and footers on or off. You can't even configure them separately.