Docs updated or added since the 1.22 release

A new Who is Dash? page!

Information about monetizing your apps has been
collected in the new Flutter Ads landing page.

Added a new page explaining the Flutter Fix
feature and how to use it.

New and updated web pages, including:
    
      Web support for Flutter
      Configuring the URL strategy on the web
      Web FAQ

The Desktop support for Flutter page is updated,
as well as other pages on the site that discuss
desktop support.

The DevTools docs have been updated. The
most significant updates are to the following page:
    
      Flutter inspector

Added a page on how to implement deep linking
for mobile and web.

Updated the Creating responsive and adaptive apps
page.

Many pages (including all codelabs on flutter.dev)
and examples are updated to be null safe.