Hi @Romain_PH ,
Could you please share a bit more about your scenario?
Which control do you use to upload your picture? "Add Picture" control or Camera control?
Further, do you mean that the error message would show up when you upload picture into your app?
Based on the issue that you mentioned, I have made a test on my side (test with "Add Picture" control or Camera control), and don't have the issue that you mentioned.
Please consider clear cache of your IE and Edge browser, then try your app again, check if the issue is solved. Also please consider take a try to open your browser in incognito mode, check if the issue is solved.
In addition, please also consider take a try to turn on the "Improved app rendering (final validation)" option within Advanced setting of App settings of your app, then check if the issue is fixed.
Best regards,