It’s not hanging and returns successfully for me. Even if it did hang no one’s going to be able to provide any help without any information. When reporting issues please provide as much necessary context to give someone some chance to be able to identify the issue. i.e. think about what information you would want to know about if someone sent this issue to you.
FYI a 1.6MB metadata download for ~360 APIs is getting quite large, your issues are likely going to be resource limitations. You may want to consider splitting your APIs over multiple Apps so they’re them more manageable.
But the browser hangs trying to render it because it’s too large. You’d need to split it into smaller chunks to make it more manageable, either by splitting your APIs into multiple app hosts or you could manually split the /openapi JSON document in multiple .json documents where you could load them individually: