I tried adding the following code to the functions.php file to change the output of an embedded Youtube video but nothing changes. I tried this with a plain WordPress install and changing to the Twenty Twenty theme and it worked with that theme but not GeneratePress.
I see that it’s not a generatepress problem as the same code is generated for both generatepress and twenty twenty themes on a clean WordPress install. There must be another plugin that is causing the change to not appear at all in one of my projects. Thanks