It's definitely not isolated to Robinhood. My problem was with a different brokerage.
I did get it working. My guess is that this issue arises when you have a large number of transactions. I had to repeatedly ask the Chrome browser to "Wait" while it loaded the form from the 1099-B. Once it finally loaded, I let the page site idle for some time before pressing continue. Eventually it got itself out of the loop. Patience appears to be key with this...
