Hi,
Sorry, I reported the problem too quickly. Everything looks fine on a clean WordPress 5.5. I think this could be a problem with a large amount of comments on my site – around 14k.
I temporarily changed the number of comments displayed in plugin settings, in the Articles section, by limiting ‘posts_per_page’ in
includes\views\export\html-hf-export-WordPress-Comments-normal.php file and everything started working.
