Changes

XULRunner is not a frozen API but instead delievers delivers a set of XUL toolkits. Some of the XULRunner applications will only work on specific versions of toolkits. The current thinking of XULRUnner version number is for it o to be matching the number of the corresponding Gecko milestone.

Developers can also be allowed to specifiy specify what is the minimum and maximum version of the toolkit is requierd required to run the specific application. This is currently implemented as an option in the .xulapp fileon Macs and in the application.ini file for Windows and Linux. The applications can specify the MinVersion and MaxVersion for the toolkit versions that is required. XULRunner will check this constraint on the application and refush to run those who do not pass the version test.