So.I was able to fix this problem at last.Change the text encoding in the tables.In my case, "latin1_general_ci" had to be replaced with "utf8mb4_gene...

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@chris This is what it looks like with me. wp_wpforo_posts.png

Thanks for the answer. Unfortunately, in "Debug Tales" everything looks fine.  Zrzut-ekranu-2021-08-13-133345.png