Onclick of button need to open popup page

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Hi,
I am working on custom widget in that I am using pdftron my requirement is on header need to add one button on the onclick of button need to open popup same as search, comments. I am able to add button on header, but I am struggling with popup page.
How can I do this?
Thanks, and Regards,
Mujaeit Pathn

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Hi Mujaeit,

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