As you were discussing with community specialist Chris _ g1 a screen shot of it :

You mean to say scroll bar is on left hand side of column , but generally it on right hand side , if there are hundred's of mail ( just an example ) you have to scroll down to find the message that is time taking job to search .
I tried and gave a solution If you choose click on A to Z the mails will be shown as starting from 1 to 100 , it means newest mail will be on top - no 1 and 100 th mail will be on last .
And , if you reverse the settings as Z to A it means 100 th mail or last mail will be shown on top and 1st mail will be shown last ( on the bottom end ) .
So , for convenience you can set A to Z or vice versa .
And also , are you concerned about the scroll bar . if yes it is a normal behavior , we have to scroll up and down .
Thanks !