Hi @ericmalloy ,
According to the official documentation, the latest version of Safari Mac is included in the browsers supported by Power BI. Please update your browser to the latest version and clear the cache and try again.
Supported browsers for Power BI - Power BI | Microsoft Docs
If the problem is still not resolved, please point it out. Looking forward to your reply.
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.