Connect Power BI Desktop app and https://app.powerbi.com/

Hi louisquinet 

Do you mean that you create a report with Power BI Desktop and have published it into your workspace in Power BI Service (https://app.powerbi.com/)? Then you want to use Power BI Desktop to edit the report that is held in Power BI Service directly? If my above understanding is correct, this is not supported.

If you want to edit an existing report that is in the service, you can edit it in the service directly. If you hope to edit it in Power BI Desktop, you can download a report copy from the service to edit it locally. Then publish it to replace the old one in the service to have the new changes. Download a report from the Power BI service to Power BI Desktop - Power BI | Microsoft Learn

If my understanding is incorrect, can you explain your process and goal with more details?

Best Regards,
Jing
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