Tapestry 5.4-beta-22

Tapestry 5.4-beta-22 contains a significant number of bug fixes and minor improvements. Dependencies on third party libraries have been updated.

• A "page loading mask" prevents interacting with the page until all JavaScript has downloaded and executed. 
• It is now possible to unregister client-side DOM event listeners.
• The client persistence strategy now detects internal changes to mutable state objects.
• Page classes may now have the suffix "Page" (but this is not part of the page's canonical name, the one used in URLs).
• Selected pages may be loaded and initialized at server startup, rather than on the first request which references them.
• Tapestry does a better job of detecting when its naming rules would cause different pages, components, or mixins to share an alias.
• There were some issues with JDK 8 compatibility that have been addressed.
• Tapestry can now be configured to work in environments, such as Google App Engine, where file system access is prohibited.
• The exception report page and T5 Dashboard pages are no longer affected when the application overrides the Bootstrap CSS files in the core JavaScript stack.
• The Dashboard page now has a "Component Libraries" page that details information about all libraries in use by the application.
• It is possible to control whether a JavaScript library is minimized, or left as-is.
• The Import annotation on a base class would not operate correctly for a subclass; it now correctly searches relative to the base class.
• The PageActivationContext annotation now works for more than one field, allowing multi-part page activation contexts.
• Exception reports may now be written, in a plain-text format, to the file system.

While not an actual release candidate, beta previews like this one are high-quality builds that pass all of Tapestry's extensive automated tests and have been voted on by the Tapestry team.