WebKitGTK+ 2.21.3 released!

This is a development release leading toward 2.22 series.

What’s new in the WebKitGTK+ 2.21.3 release?

• Ensure memory monitor properly notifies all child processes.
• Add maximize, minimize and fullscreen window commands to WebDriver.
• Fix a network process crash when trying to get cookies of about:blank page.
• Fix UI process crash when closing the window under Wayland.
• Disable Gigacage if mmap fails to allocate in Linux.
• Fix several crashes and rendering issues.

Thanks to all the contributors who made possible this release.