I already answered your support thread which contained one more question about RadMenu and for your convenience I pasted my reply below:
Straight to your questions:
- I suggest to try setting for all your RadSplitters (main and nested ones) the VisibleDuringInit property to false. This should hide the splitters until all the calculations have ended and the splitters have been initialized.
- I examined the attached screenshot but it is not enough to help me provide a fix for the problem. You say that the problem exist only under FF and not under IE and this makes me assume that it is due to positioning settings instead of z-indexes. Would you please examine the positioning settings by using the Firebug tool and try solve the problem by changing them? In case this does not help or you need further assistance, please send me a sample, fully runnable reproduction project and the version of FF in which the project does not work. Once I receive it, I will modify it in order to meet your needs.
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