SSMS in SQL 2016 has come up with lots of new features. One of the features is enhanced scrollbar in SSMS. I personally believe the new enhancement in scrollbars will definitely help developers to work with SSMS with ease.

Let us look at the below picture to have an insight:

They are different color bocks on the right side of SSMS query window that shows the changes:
a. Green blocks show the saved lines of Query part in a window to disk
b. Yellow blocks show the query lines of unsaved/changed lines since last save to disk
c. Red blocks show any syntax errors in a query window
d. Blue block shows the current cursor location

It is definitely good to know to developers who plays around with SSMS very frequently.