Open chrome developer tools by pressing CTRL+SHIFT+I and navigate to console panel. Copy the code in hackerrank-leaderboard.js file and paste it in console panel.
Replace the value of the contestCode variable in line 34 with the contest code. You can get the code from hackerrank contest URL. For example, https://www.hackerrank.com/contests/101hack52/leaderboard. Here 101hack52 is the contest code.
Then, replace the value of numberOfPages variable in line 35 with the number of pages in the leaderboard.