I followed this Microsoft tutorial to embed a PowerApp into a SharePoint page. It was super easy to do. The SharePoint page has been under testing for a while, and while performance is fine on Chrome and Firefox, Edge and IE have been very sporadic.
I haven't gotten Edge to display the embedded piece or the web part ever. IE works on and off without any changes (just refreshing the page...and sometimes if you refresh it even after it works it will break). Sometimes the Page Viewer will load, sometimes it will load in perpetuity, and sometimes it breaks (see the screen grabs below). The embedded piece in IE hardly ever works. It either just keeps loading or randomly will work on a refresh.
Are there any known solutions to these issues? This app is just to submit an approval request for a meeting. With flow and the power app, we've created an awesome setup but the end users are technologically challenged and we need it to work consistently.
This is what Edge web part and embed errors look like: 
| IE Error Perpetual load embed: 
| IE Error Web Part:  |