Firefox 3.6.8 for Mac and FCK 2.6.6 ASP.NET

[oliver]

If I mark a word in Firefox 3.6 Mac the FCKEditor adds automatically the following <p>-tag at the end of the text-box.

<p><img id="fvdkoff-target-image" style="position: absolute; visibility: visible; color: transparent; margin: 0px; border: medium none; z-index: 2147483647; left: 336px; top: 1472px;" src="data:image/png;base64,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" alt="" /></p>

When I mark a word there comes a small blue sign in the right corner above the marked word:

This only happens under Firefox 3.6 Mac. With Apple Safari it doesn`t occur. Do you have an idea what the reason is for this failure of FCKEditor?

[oliver]

Screenshot Firefox 3.6.8 Mac when a word is marked

[oliver]

Source Code at the end of a text box where FCK adds a p-tag

[Alfonso Martínez de Lizarrondo]

That's some extension that you have installed in Firefox. You should be able to recognize that image as that will be used in the normal usage of that extension.