Don’t just override opacity with null , it will override whatever the original style was. Before setting to 30% you need to store the original value and restore that in the timeout.

At the bottom of that page the author lists some tools that can fix apps that don’t respect this.

libetc - uses a .so to reroute syscalls that try to access files in $HOME, but this hasn’t been updated since 2018 boxxy - calls the tool in a Linux namespace with bindmounts to reroute files. This seems maintained but you need to alias commands like alias aws="boxxy aws"

Every tool author should use https://xdgbasedirectoryspecification.com/