All pages (including editing) appear completely empty once logged-in

[evolverine]

Starting a private session shows the expected homepage, then after logging in becomes a completely blank page. The debugger shows a few errors:

No record found at path humans/1PJ15tjDvJn5uqtHXNRSj4fwHSNNotvDQ Error: Missing readURL
POST https://hub.blockstack.org/store/1GFmjjdgmFoF3mKEdojxUVZvTxN7Jq1tuv/humans/1PJ15tjDvJn5uqtHXNRSj4fwHSNNotvDQ - status code 412 Precondition Failed, error "The entity you are trying to create already exists"
[LOTS OF:] Uncaught PreconditionFailedError: Error when uploading to Gaia hub. If you believe this exception is caused by a bug in blockstack.js, please file a bug report: https://github.com/blockstack/blockstack.js/issues