Power bi - Power apps problem

Hi Yomzy1 , Thank you for reaching out to the Microsoft Community Forum.

This usually happens when the embedded app is doing a full cold start each time the iframe loads. That delay typically comes from heavy work in the app’s OnStart (large queries, sequential connector calls or big images) or from the app having to renegotiate authentication inside the embedded Power BI frame. Either of these can easily push the load time to 15, 20 seconds. The quickest way to confirm the root cause is to reproduce the issue with your browser DevTools, open and compare it to opening the app directly in Power Apps. If you see long XHR or OAuth calls, the delay is coming from the app/auth cold start; if the iframe sits idle with no heavy activity, the slowdown is coming from the embedding layer in Power BI.

The fix depends on what you find, but the safest optimizations are to move expensive work out of OnStart and load it lazily in OnVisible, run independent calls in Concurrent(), cache data so it’s not repeatedly downloaded and trim heavy media on the first screen. Also test in an incognito window or another browser to rule out extension and caching issues. If your DevTools trace shows delays that aren’t caused by your app, collect a HAR file, note the timestamps, include your OnStart code and any bookmark parameters and open a Microsoft Support ticket , so they can check for an embedding or auth-side regression.

Below is the link to help create Microsoft Support ticket:
How to create a Fabric and Power BI Support ticket - Power BI | Microsoft Learn