Swapped over to Prism Launcher and used it to update all my mods and now the instance is not starting. Disabling Memory Leak Fix lets it start as normal so I'm wondering what's causing the issue. Please and thank you for any help!

https://mclo.gs/Ef6tnVb

Downgrade to Version 1.1.2 or below, should fix it.

Downgrade to Version 1.1.2 or below, should fix it.

Can confirm this works for me! Thank you bro!