Hi,
I had a tabular theme going in experience builder where I am embedding multiple dashboards, however, as of this morning it is no longer working as expected. This worked great last week - I saw there was a recent update that changed some things, but why would this be impacted? It is coming from our ArcGIS Online, same place experience builder is located. I tested the embed functionality in Story Maps & Hub - they were fine still.
Also of note - same thing seems to be happening to this Covid Experience linked on your site - I am not the only user impacted:
Experience
