Large Configurable: Failed to load resource: net::ERR_CONNECTION_CLOSED Issue in Magento 2.4.4

[FatehMomin]

I have some configurable products with up to 100  simple products. Since my last upgrade, I have been

unable to add any more simple products to any configurable with more than a few hundred existing products.

As soon as I click the "Add Products Manually" link, I get the "Something went wrong error". and the system is unable to list products to be added (infinite spinner) There is no log information in Magento for the error or in mysql/php logs.

[Bad3gg]

I hit this problem a while back.

https://community.magento.com/t5/Magento-2-x-Version-Upgrades/Admin-Large-Configurable-Failed-to-loa...

That should help.