Issue
Select file section on Document Package does not load/being blocked by browser.
Resolution
In your browser URL, click on the lock image located at the beginning of the URL.
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.
Navigate back to the Salesforce tab and refresh the page.
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.
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.