Issue
Select file section on Document Package does not load/being blocked by browser.
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Resolution
In your browser URL, click on the lock image located at the beginning of the URL.
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Then click on Site settings – A new tab will open to display Chrome settings.
Under Permissions find the Flash section.
Click on the dropdown and select Allow.
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Navigate back to the Salesforce tab and refresh the page.
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Then click on Site settings – A new tab will open to display Chrome settings.
Under Permissions find the Flash section.
Click on the dropdown and select Allow.
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Navigate back to the Salesforce tab and refresh the page.
Additional Information
Nintex Drawloop is prepared to deal with this issue! Check out LEDD (Lightning Experience Document Designer) As of 8/23/19 this is still in BETA mode. You can test in your Org with ease, by simply flipping a switch. As mentioned this is still in BETA and our team is working hard to iron out any/all issues.