Hi,
Thanks for your inquiry.
Here are the answers to your questions.
(1) PdfViewer control can't control showing or hiding "open pdf file" button, its functional design cannot be changed now. But you can use PdfDocumentViewer control and use a button to achieve it. Like the screenshot below.
1.png
(2)Sorry, the tooltip text is available only in English at present.
Sincerely,
Amy
E-iceblue support team
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