Hello,
We require to migrate existing solutions ( SSO/CSO ) for modern portals using SPFx or other approaches that supports modern pages in On-premises version of SharePoint Server 2019, while making sure that it will also work for SharePoint Online.
There are number of documents for specific solutions/situations, while I am looking for a particular strategies to follow and guidelines to decide the solution development approaches for the modern sites, Can you please share any such details if it's available?
Best Regards,
Dipti Chhatrapati