Steps to reproduce in app:
We use a dashboard where a list element filters an embedded content element (HTML infographics). That embedded content element throws the "progressbar nodes" error when testing with Axe as well as "Frames must have an accessible name," even though we assigned the element alt text in the dashboard editor. Again, thanks for documenting!
This issue was fixed in the last release of Arcgis Online https://support.esri.com/en-us/bug/arcgis-instant-apps-was-scanned-using-axe-devtools-whic-bug-00018...