What happened to the greyed out save button?

It used to grey after I saved which was really helpful. Now in the latest version there is no change. I am going to revert to an older version.

https://cgit.freedesktop.org/libreoffice/core/commit/?h=libreoffice-5-1&id=677197b3459df2c89be32595e0cb1b8b3e144c69

I don’t have enough points to upvote but I have the same question/concern

There is an disk icon in the middle of the bottom toolbar that changes from grey to red.