This is from the Organize window- it shows the settings for viewing your content by its safety filter setting- in this instance, view all the images classified as Moderate.
Prior to my restriction being lifted, ALL my photos showed up when viewed this way. I selected all the ones I wanted to change to Safe and dragged them up into the Organize section of the window. From there I went to the tabs at the upper edge of the Organize section, and clicked on Permissions. In the resulting pop-down menu I selected Set Safety Filter. In the window that opens click Change Safety Filter and everything you've selected will be reset to safe.

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This is the Organize button with its pop-down menu options shown. Click directly on Organize itself or click the little triangular disclosure button to see the options then click on the specific function- All your content.

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This is from the Organize window. Click the "more options" link to the right of the Search button. That reveals the additional options for viewing and sorting your content.

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Drag the images you want to change into the main part of the Organize window. Then click the Permissions link and click Set Safety Filter.

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When you select Set Safety Filter, you get this window. The Safe button is selected by default. If you are changing all the photos back to Safe, just click the "Change Safety Filters" button.
This should reset the restriction setting from Moderate to Safe. It did for me, once I was notified that the restriction had been rescinded.

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