Mark Finkle released today version 0.7 of WebRunner, a XULRunner based application that allows to run single web applications in an isolated environment without all the navigation, configuration and much other user interface browsers typically feature.

If it sounds like just a crippled browser, well to some degree it is but it provides some benefits full featured browser like Firefox can’t. For example, in a business environment it will help web apps users focus on this application instead of keeping jumping around several other web sites. Web links taking to sites other than the requested web application launch in the default browser. This alone provides protection from cross site scripting attacks where a malicious web site hijacks data from another frame or embedded web page.

WebRunner is basically an empty window. To activate a web application you will need a web application definition file (.webapp), a renamed zip archive with files that provide details like the URL of the web application, an icon and most notably, some JavaScript you may want to run to configure WebRunner’s sober feature set and user interface. For example, the Gmail web app, one of the examples provided by Mark adds a cool notification message and beep (OK not that cool) when you have new email.

Other examples include Google Docs, Google Groups, Facebook, Twitter and others which you just need to download and run and WebRunner will open them. Hopefully some other useful web apps like Yahoo! Mail and Meebo will be made available soon.

Once the web app is launched there’s very little to say about it beyond its own capabilities. WebRunner provides a status bar icon that pops a menu with options to print the web page and add a shortcut icon to your desktop or QuickLaunch bar (on Windows) which uses the bundled icon mentioned before and the recommended command to launch it more quickly.

This latest version also adds support for the sidebar and makes the statusbar visible at all times. Future enhancements include extensions management, spell checker, form saving and possibly a separate extension to create .webapps in Firefox.

I noticed the Gmail app stays logged across WebRunner sessions and I wonder if it’s by design or a just in expected bug at this time in development, but I think in the context webapps are been developed it would make more sense to (somehow) close sessions. We’ll see.

You can get WebRunner Mozilla Wiki. Just keep in mind it is alpha or beta quality at best.