Move to modern experience in SharePoint and what you need to know about it

Modern experience in SharePoint

Microsoft offers a good overview about all topics in this context on this website: https://docs.microsoft.com/en-us/sharepoint/guide-to-sharepoint-modern-experience This article is structured with the following headlines: Information architecture and hub sites, Navigation, Branding, Publishing, Search, Sharing and permissions.

I already posted about some of these topics:

• Information architecture and hub sites => Summary about Modern Team Sites, Communication Sites & Hub Sites
• Branding => Summary about Modern Team Sites, Communication Sites & Hub Sites
• Sharing and permissions => Coaching your users through the External Sharing Experience

Other topics:

• Navigation: The “inherited” navigation feature in classic SharePoint site is not available in the modern experience. Hub sites provide another way to achieve cross-site navigation previously available in managed navigation and site hierarchies in classic SharePoint. 
• Publishing: In the modern experience, Communication sites replace traditional publishing sites. Communication sites are easier to build and maintain, and include new features such as a modern authoring canvas. Also multilanguage capabilities will be available soon. They allow you to. To sum up: you can quickly create beautiful and responsive pages to share news, reports, statuses, and other information in a visually compelling format - all without heavy developer investment. You can get inspired with some great examples in the SharePoint Lookbook.
• Search: SharePoint has both a classic and a modern search experience, where Microsoft search in SharePoint is the modern experience. Microsoft is actually in the middle of a transition from Classic Search to Microsoft Search. Because of this there are other differences, especially around customization. More details: When to use which search experience. The most visible difference are:
• Microsoft search box is placed in the header bar
• Microsoft search is personal. The results you see are different from what other people see, even when you search for the same words
• Search as you type: And you'll see results before you start typing in the search box, based on your previous activity and trending content in Office 365

Modernize your root site

A root site, f.e. https://contoso.sharepoint.com, which is set up before April 2019 was created as a classic team site. Now, a communication site is set up as the root site for new organizations. If your Office 365 Tenant was created before April 2019, you can modernize your root site with one of these scenarios:

• Replace the root site with a new site: If you already have a site that you want to use as your root site, or if you want to use a modern team site, replace (swap) the root site with it. This scenario is very useful if you plan to create a new site and let the old one live until you are ready. We can use the new SharePoint admin center to replace the root site. Select your root site (f.e. https://contoso.sharepoint.com) in the Active Sites menu in SharePoint Online Admin Center. Doing this you get the “Replace site” button in the menu:

Selecting this you get the following dialog:

And we can also use PowerShell to do the swap. Powershell offers the capability to manually set the url for the archive url and some further parameter:

Invoke-SPOSiteSwap

         -SourceUrl <string>

         -TargetUrl <string>

         -ArchiveUrl <string>

         [-DisableRedirection]  

      [<CommonParameters>]

 Details & Examples: https://docs.microsoft.com/en-us/powershell/module/sharepoint-online/invoke-spositeswap

• Use the root site as it is but with a modern experience: If you want the content on your classic root site as it is but want to have the layout of a communication site, apply the communication site experience to the root site. This feature isn't available yet but is coming soon.
• Continue using the classic team site but with modern pages library and a modern home page: If you want to continue using the classic team site, enable the modern site pages library experience and set a modern page as the home page of the root site. This gives users a modern team site experience with the left navigation.

Things to think about

Before you begin, make sure that…:

• If you have "Featured links" on the SharePoint start page. You'll need to add them again after you replace the root site.
• Review your source site about policies, permissions, and external sharing settings

Limitations:

You can use the following as a new root site:

• Communication site (SITEPAGEPUBLISHING#0)
• Modern team site that isn't connected to an Office 365 group (STS#3) | The root site can't be connected to an Office 365 group.
• Classic team site (STS#0).

When plan to do a site swap the root site and the new site can't be hub sites or associated with a hub. You need to unregister it as a hub site, replace the root site, and then register it as a hub site again.