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There was one extension, an Acrobat PDF 1.2 extension. Disabled, then rebooted Firefox and tried again. Problem still exists.
There are also a number of plug-ins. I disabled these as well, and rebooted. None of these worked.
Finally, I enabled HTTPS. I doubted this would be a problem, since 99-100% of my work takes place at home in a secure environment.
None of these worked to solve the problem. My editing page looks very similar to americanelephant’s page, with the boundless edit module and no scrolling bar. I use two columns as he does, and usually, the second column will fold under the first column, if I make the screen window narrow.
Thanks again. I hope we are making progress. I use Firefox 17.0, and am up to date.