I've seen some posts both on Joomla and here in this forum concerning this. I had the same problem whenever trying to access any page that used the content editor. I solved found my problem and thought I would post my experience in case others need help. If this isn't the right place, then I apologize.
I would get the ondisplay error at "editor.php on line 263". It appears to be caused by some plugins that add features to your editor. I don't know why. I haven't explored it closely. In my case it was the "add button" plugin for Seyret. Others have had problems with DocMan and other plugins.
So, if you get this error in VirtueMart, I suggest the first place to look is for enabled plugins that modify your editor.
HTH
Thank you for the info.