I am seeing an error in the web console on a particular site that I do not see in any other browser (Safari / Chrome / etc). See the screenshots below
Web console:

Page source on line 43

No errors like other browsers on the same page.
FYI, this is not having a negative effect as far as I can tell so functionally it is working for me but might cause unintentional behavior elsewhere. Obviously there is an issue with a script.
I have ublock origin extension installed but disabled for this site.
Version 1.0.4 (143.4-rc), WebKit 624.1.7