Thx Shea Bunge for that plugin.
But it does not work in 3.5.1: I wrote a simple snippet, my first snippet and activated it: all(1) active(1)
In my page I insert: [testsnippet]
I saved it, running that page resolved the output: [testsnippet] and NOT the code in snippet "testsnippet".
I'm trying since one hour. Normally such a simple error is because of fault of the user (me!). But I checked anything some dozends of times! I changed the name of snippet. I deactivated, I activated again. No success!
Perhaps not working in 3.5.1 ?