Lightning widget is not visible
First of all, take a note that Lightning widget is not visible to users, that do not have rights to modify store settings (setting/setting).
If your admin is modified to use another template, Lightning may not be able to show the widget.
With Lightning 3.09 and higher you can access Lightning widget directly by URL: http://myshop.com/?lightning or by clicking the modification title:
Nice to hear that!This info will be shown more often to another people.
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