Vanish will no longer present a button to use with Admin Panel due to the change of permissions within Vanish. I changed this line...

private const string permVanish = "vanish.use"; 

to...

private const string permVanish = "vanish.allow";

This change has made Admin Panel functional again for Vanish.

My man! Thank you @Z1PP3R

Before Update I had a Button like the most others to vanish with the Admin Panel Menu but since update there are all other buttons only vanish not.
I can vanish with the chat command and also unvanish but not via clicking on the button
How to fix that?

greets

same issue here 

Making the change outlined by OP resolves the Vanish button missing from the GUI issue.

This will be fixed in 1.4.1

Thanks for the fix Nivex and for all the other mods you work on as well. Keep kickin' ass and takin' names really appreciate it!

Lol, you're welcome