This is with build 2001050710. After opening a local HTML file (e.g. file:///home/fozz/something.html) and printing it, I opened a plain text file (e.g. file:///home/fozz/somethingelse.txt) and printed it. The HTML file printed just fine. The text file printed with a page header including the document title from the previous HTML file printed. It seems this information (the title) is getting cached somewhere and isn't getting removed when a new document is loaded which may not be HTML.
*** Bug 80886 has been marked as a duplicate of this bug. ***
*** This bug has been marked as a duplicate of 71976 ***