Hi @ReneAubut,
It is not currently possible for the author or user to change the default folder for the image browse option when the folder icon is selected. The folder will always default to the default application folder on Windows.
We have an internal issue in our backlog to change the default to C:\Users\xxxxx\Pictures\ for Windows specifically, and this is something we may be able to address in a future release. If you could please raise this as an enhancement with Esri Support, that would be benefical in getting this enhancment prioritised and hopefully into a future release.
Regards,
Phil.
