I started to find the reason of the problem on Friday and I continue it now.
Today I realized that the earlier missing elements are displayed now (please find the attached screenshot).
Have you changed anything since Friday that resolved the problem?
I have not done anything (except deactivate and activate the plugin, and add a “WP Related Items” widget to your Right Sidebar, to get a similar result to your attached screenshot.)
If I have to do anything else to continue to resolve this issue, please let us know.
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