Attempt to invoke VE by clicking the Edit button on my near-empty user page http://en.wikipedia.beta.wmflabs.org/wiki/User:Cmcmahon, get error:
Error loading data from server: internal_api_error_ErrorPageError: Exception Caught: <editpage-notsupportedcontentformat-text>. Would you like to retry?
Note: several hours ago a number of automated browser tests failed by timing out waiting for 10 seconds for the diff viewer to manifest in the browser. There may have been a performance problem before this error appeared.