As I have mentioned previously, a scroll bar will appear when I place an Amazon "iframe" ad in Scribefire Chrome for Opera, resulting in the ad not being displayed as it should while editing, and indeed after publishing, while in "Edit Visually" mode.
After having gathered enough courage to peek at Scribefire's source code, I am glad that I have found a fix to this problem (see Note 1 below on extracting the source code from the Scribefire Extension file "scribefire-4.oex").
This is what I did to remove the scroll bar. I appended additional parameters to line 964 in the file "events.js" - they are actually just parameters found in the code given by Amazon that were not defined in this line. Below is how the line looks before modification:
extended_valid_elements : "iframe[title|width|height|src|frameborder|allowfullscreen]",
My modified line now reads: