When the leaderboard page is pulled up the screen is blank.
Leaderbord is working in most languages but not English. You could switch to Afrikaans, looks like that language is all English and the leaderboard works.
I recently had to downgrade Firefox to version 65, when I had this issue - several websites caused problems like it.
If you're using Firefox, you can download v.65 & use it for a couple of weeks until (hopefully) a newer version fixes whatever was an issue...
Or try Chrome, which works nicely on this site.