- let the upload dialog box stay in place until the upload was successful
- if metadata is faulty, tell the user to correct them (e.g. invalid vocabulary)
- show which metadata is mandatory and which are optional
- if metadata is faulty, tell the user to correct them (e.g. invalid vocabulary). This involves the backend to check as much as possible.
- show which metadata is mandatory and which are optional. Mandatory metadata is marked as such in the propertyAssignments that are fetched from the backend (e.g. `"mandatory:true`)
- if dataset type is changed back and forth, keep the values that already have been entered