One click scroll buttons at the ends of scroll bars.

Great Comments Norbert.  It is surprising how useful those little arrows really are.  One big example is the program "SnagIt"  a screen capture program (fantastic program by the way!)  One of its big features is being able to capture more than what is shown on the screen.  You can set an auto-scroll capture where you mark you "upper-left" corner then you click the scroll arrow in the direction you want to scroll and it auto-scroll's the window to capture the whole page.

Making the arrows optional is a good idea.

Scrollbar arrows for Web Player were already removed in 6.5, looks like Prof Client only followed the trend a version later. Our users also disliked the change and we raised a support case for the same, but no change was implemented to address this (SR id: 532945). 

Worth mentioning that at one point Google also removed the scrollbar arrows from the Chrome browser - users were furious and raging on different channels and forums, so Google decided to add back the arrows a couple of versions later:

http://www.cnet.com/uk/news/chrome-users-mad-at-google-for-switching-up-scroll-controls/

https://bugs.chromium.org/p/chromium/issues/detail?id=294543 

http://www.ghacks.net/2014/01/18/restore-scroll-bar-arrows-google-chrome/

To me, this is the same story just in a smaller scale so user complains are not loud enough to be heard. Ideally this could be optional, so a checkbox under Edit -> Document Properties -> General tab could control whether to display scrollbar arrows or not (just like the 'Auto-hide scroll bars in table visualisations' option which also modifies the UI behaviour)