Products with Generic child variant childreen undisplayed

[--Joao--]

Hello
I have a problem with products undisplayed in the category, when they have Generic Child Variant products.
After several tests I found that in a default Virtuemart installation, with sample data, the same problems happens just by saving the configuration settings even without any modification.
Can any one help me how to turn around this problem?

index.php?option=com_virtuemart&view=category&limit=500&page=shop.browse&virtuemart_category_id=0
61 products exhibited (default sample data installation)
52 products exhibited (after clicking SAVE in the configuration settings)

Thank you

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VirtueMart
3.8.4 10335
PHP Version
7.3.19
Joomla! Version
3.9.21
mysql
5.7.29-cll-lve