For the 1.9 release, Flutter’s web support has been merged (“unforked”) into the main repo. Web support hasn’t reached beta, and is not ready to be used in production. Web and desktop support (which is also coming), will impact the website, which was originally written exclusively for developing Flutter mobile apps. Some website updates are available now (and listed below), but more will be coming.

New and updated docs on the site include:

We’ve revamped the Showcase page.
The Flutter layout codelab has been rewritten and uses the updated DartPad, the browser-based tool for running Dart code. DartPad now supports Flutter! Try it out and let us know what you think.
A new page on using the dart:ffi library to bind your app to native code (a feature currently under development).
The Performance view tool, which allows you to record and profile a session from your Dart/Flutter application, has been enabled in DevTools. For more information, see the Performance view page.
A new page on building a web application.
A new page on creating responsive apps in Flutter.
A new page on preparing a web app for release.
A new web FAQ.
The Flutter for web page is updated.

Other relevant docs:

Error messages have been improved in SDK 1.9. For more information, read Improving Flutter’s Error Messages on the Flutter Medium publication.
If you already have a web app that depends on the flutter_web package, the following instructions tell you how to migrate to the flutter package: Upgrading from package:flutter_web to the Flutter SDK.
A new ToggleButtons widget, described in the API docs. ToggleButtons demo
A new ColorFiltered widget, also described in the API docs. ColorFiltered demo
New behavior for the SelectableText widget.

Happy Fluttering!

What’s new archive

New to Flutter?

Once you’ve gone through Get Started, including Write Your First Flutter App, here are some next steps.

Docs

Coming from another platform? Check out: Android, iOS, Web, React Native, Xamarin.Forms

Building layouts: Learn how to create layouts in Flutter, where everything is a widget.
Adding interactivity to your Flutter app: Learn how to add a stateful widget to your app.
A tour of the Flutter widget framework: Learn more about Flutter’s react-style framework.
FAQ: Get the answers to frequently asked questions.

Videos

We also have some helpful videos on our Flutter Youtube channel! In particular, check out the Flutter in Focus series, and learn about other series on our videos page.

First up, why use Flutter? What makes it different than other app frameworks?

How is Flutter different for app development?

Flutter in Focus: Learn Flutter features in 10 minutes or less.
Flutter in Focus playlist

In Flutter, “everything is a widget”! If you want to better understand the two kinds of widgets, Stateless and Stateful, see the following videos, part of the Flutter in Focus series.

Want to skill up?

If you learn best by watching engineers write code, make mistakes, and fix them, check out the Boring Flutter Show video series:

Boring Flutter Show playlist

You might also find these docs useful: