Saul Hi Saul, sorry for the late reply.
The interesting part is that it's trying to prepend an element, I'm only unable to find what element. Are you able to click the link at the error (
dashboard.min.js?v=a0dfa&ver=5.2.3:66) and make a screenshot of the code where the error appears (with the red circles under the code)?
That would be very helpful!