How do I prevent closing of locked tab?

[Leo]

This script add-in blocks closing locked tabs:

Acecool Proper Tabs - Prevent closing locked tabs

Tabs don't behave the way I expect them to behave so I'm writing a script to correct this. There are a few issues I've run into but I am working on resolving them. I am also looking into a way to add configuration to the scripts without requiring use…