PowerBI embedded dashboard greyed out in model driven PowerApp

This is quite possibly a PowerBI newbie question. My embedded PowerBI dashboard shows completely greyed out in my PowerApp (though looks fine when viewed on app.powerbi.com in the same browser instance as the same user). If I embed just the underlying PowerBI report in my PowerApp, it renders fine. I have a PowerBI pro trial license and am running the latest stable Chrome as of today (Version 89.0.4389.128 (Official Build) (64-bit)). When I look in the developer console in Chrome I see the following stack trace (can't say if it is relevant or not as there are other 404s and 401s). I saw one other post/support query in the community with an inconclusive answer (i.e file a support ticket 😉 ).

Has anybody seen anything like this? 

ERROR Error: Uncaught (in promise): TypeError: e.headers is not a function
TypeError: e.headers is not a function
at e.handleUserDoesNotBelongToCurrentCluster (dashboardEmbed.min.c74ea9429332a1008265.js:1)
at dashboardEmbed.min.c74ea9429332a1008265.js:1
at t.invoke (powerbiportal.dependencies.externals.bundle.min.dc17c7ce5bd0a6cd082e.js:5)
at Object.onInvoke (dashboardEmbed.min.c74ea9429332a1008265.js:1)
at t.invoke (powerbiportal.dependencies.externals.bundle.min.dc17c7ce5bd0a6cd082e.js:5)

..........

ERROR Error: Uncaught (in promise): [object Undefined]
at _ (powerbiportal.dependencies.externals.bundle.min.dc17c7ce5bd0a6cd082e.js:5)
at _ (powerbiportal.dependencies.externals.bundle.min.dc17c7ce5bd0a6cd082e.js:5)
at powerbiportal.dependencies.externals.bundle.min.dc17c7ce5bd0a6cd082e.js:5
at t.invokeTask (powerbiportal.dependencies.externals.bundle.min.dc17c7ce5bd0a6cd082e.js:5)
at Object.onInvokeTask (dashboardEmbed.min.c74ea9429332a1008265.js:1)
at t.invokeTask (powerbiportal.dependencies.externals.bundle.min.dc17c7ce5bd0a6cd082e.js:5)
at e.runTask (powerbiportal.dependencies.externals.bundle.min.dc17c7ce5bd0a6cd082e.js:5)
at m (powerbiportal.dependencies.externals.bundle.min.dc17c7ce5bd0a6cd082e.js:5)

......