You can create a widget that displays a list of communities a user has access to. You can set it so that it shows communities that you have specified, and you can pin communities to the start of the widget so that they are always visible to users when viewing the widget.
Example: If you have a homepage configured for users who have a “New starters” option selected in their profile, you might configure the widget to display lots of useful communities that can help new starters get oriented or communities with lots of useful resources, and then add this to that homepage so that they see them as soon as they land there.
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