Dashboard is not savable

One of my dashboards can’t be saved
Actually there is no even a “Save” button on it
It is editable though
Why? How to make it savable ?

Go to dashboard settings, make it editable first and follow instructions:

Maybe dashboard is provisioned.

They are both editable, and they are both provisioned
There are two of them, and one is savable, but another is not. wtf?