Thanks...I went to Bugzilla and discovered that this is a known bug in Firebird/Mozilla. You can get more information by searching for Bugzilla Bug 214250. Later, Mike

This seems to be a bug in Firebird. I tested version 0.6.1 on Windows. I found that if I double-clicked on my test file, there was a history object and it had the right methods. But if I loaded some other page first, then loaded the test file, there was no history object. However, Mozilla 1.2.1 worked correctly. I do not have a more recent version of Moz on this system to try, so it might be a bug in Moz rather than Firebird per se.