Hi Christophe,
Thanks for contacting Syncfusion support.
We have tried to reproduce the reported issue by configured the Syncfusion NuGet feed links and click the Manage NuGet packages option from project like yours. But, we were not able to reproduce the reported issue from our end. Please refer the below screenshot for reference.
Please update the below details to proceed further.
- Screenshot/Video for the issue reproducing.
- Details about your Visual Studio. Select the Help->About Microsoft Visual Studio. Copy the Visual Studio information by clicking Copy Info and paste this information into notepad. Also, System Information by clicking the System Info and paste into notepad. Share those Visual Studio and System information also.
- Nuget.Config file which is available in the below location
Windows: C:\Users\UserName\AppData\Roaming\NuGet
Mac: ~/.config/NuGet/NuGet.Config
Regards,
Ganesan R.