Sometimes the scan finds mixed content in widgets. If you see this message it’s likely there’s a link to an image in one of your widgets which isn’t available over https://. The scan helps you locate the widget in which the mixed content is found. In the screenshot below you can see a result from the scan:
First the file which cannot load over https:// is shown. Beneath the link the scan details two things: the widget area in which the mixed content is found and the title of the widget in which the mixed content is found. Clicking the first button after the results (edit) will take you to the WordPress widgets page. In this example the mixed content is located in the ‘Primary Widget Area’ in the widget that has ‘Mixed content widget test’ as a title. The mixed content can be fixed by downloading the image and adding it to your own media library. Before doing this, make sure you have permission from the copyright holder. When the image is hosted on your own domain (or another domain which has an SSL certificate) the link in the widget can be edited and the mixed content should be fixed.