We are aware of the reported issue and it is connected with the inabily of the Android browsers to read PDF files. You can experience the same behavior with a standard <iframe> element (what is also the element we are using to render external content in RadPane), loading a PDF file:
You can find more information on the subject in the following StackOverflow thread: How to open pdf file inside android browser?
On a side note, I would like to mention that using a Splitter with only one RadPane is highly not recommended scenario
that is not supported and might lead to many unexpected issues.
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