Power BI embed in website with app owns data + master user

Hello everyone,

This is the first time I am reaching out for help on this forum. I've been searching for solutions for the past 2 weeks and haven't found anything.

I used to embed my Power BI reports in a website (usually using this WordPress plugin : https://wordpress.org/plugins/embed-power-bi/) with the app owns data method combined with a "master account" authentification beared by the website. I am also familiar with the Azure AD "App registration" configuration and everything worked perfectly until the begining of last week (5th of June). In addition, I have been using this setup for a few years now and never add any issues.

I am now faced with an error when I try to use the same setup (that has been in prod for several months now): "An error occurred, please try to open the report again. If problem stays, contact support and give out the details below:

• ID de requête : ee3b6444-2897-4d6c-a98f-cb7ee7ce2e8d
• Heure : Tue Jun 13 2023 14:15:31 GMT+0200 (heure d’été d’Europe centrale)
• Version du client : 2306.1.14294-train
• Message d‘erreur : resolveCluster Exception: Failed to execute 'setRequestHeader' on 'XMLHttpRequest': 'Bearer ....... is not a valid HTTP header field value.

I have also tried to use the code given by Microsoft for Power BI embed with app owns data but without success.

My app is correctly setup in Azure AD, correctly connected to the Power BI Service workspace and has all the rights required. My "master account" has a Pro licence. I however have no capability related but it was never mandatory before...

Any idea or suggestions? If you need more info do not hesitate 😉

Thank you in advance,

Have a nice day,

Jules