I just quote from the WiFiNINA web page
For easier WiFi connections, from version 1.3.0 the library supports AP Provisioning: if there is no known WiFi network, the module sets up an AP to which you can connect and choose one of the WiFi available, input the credentials, store them and then connect to it. The firmware from version 1.3.0 onward also supports a Storage class, allowing you to store on the module's Flash memory data up to 256KB; it works as our SD class.
I cannot find any information on the 'Storage class' & how to initiate it.
Also the AP Provisioning function does not seem to be implemented in firmware 1.4
I have updated my MKR 1010 to firmware 1.4
Can anyone show me where the Storage class is implemented in the arduino libraries
and does anyone know about the missing function