The problem
Okta is set to release version 4.2.0 of their Sign-In Widget, which is incompatible with RV 7.3.4 and earlier. We can’t provide you with a date for this release by Okta, as this happens over a span of days on their end.
Note that you may also be affected if you are running the Shotgun Desktop, but that the Shotgun website and Shotgun Create are NOT affected.
How can I prepare?
Update RV to a newer version. The latest version of RV can be found on your Shotgun site under the Apps menu, or download it directly from www.tweaksoftware.com/downloads
Troubleshooting
If you encounter an issue after the update, please contact support@shotgunsoftware.com.