Reading example codes with line numbers is currently difficult because the line numbers are shown in individual lines with code below it. It is preferable to have line number in the same line as the code. Please see the screenshots below for clarity.
I could get the line numbers to be displayed on the same line by editing bootstrap-mediawiki.css line 568 and removing the "list-style-position: inside;" style. Please look into this and edit the file on the server to display example codes in better manner.