Fried Fish

What does this mean for Firefox and Thunderbird, and how does this compare/relate to the GRE? I'm not sure I get it.

XULRunner allows Mozilla-based applications to be written without writing a single line of C++ code. Whereas the GRE is a set of DLLs, XULRunner is a complete application container (much like java.exe).

XULRunner is basically Firefox minus some chrome (XUL, JS, CSS, XML, etc.) files and a little bit of C++ code. Both Firefox and Thunderbird could be modified to run as applications on top of XULRunner. They would then share considerable code with one another, which means reduced overall download size for both applications and reduced memory footprint when both are running at the same time.

The GRE also has the benefit of sharing code, but unlike GRE based applications, XULRunner can statically link to Gecko, which means smaller download size, smaller footprint, faster startup times, etc. That said, it's completely possible to implement XULRunner on top of the GRE, and that may happen in the future (although likely the GRE would have changed significantly by then).

NOTE: Unlike the JRE, each XULRunner based application runs in its own process.

Does this replace XRE or are they the same?

XULRunner is in effect a thin executable wrapping the XRE. The XRE had to be modified and extended slightly to support XULRunner, but XULRunner itself doesn't really add any code. Instead, it simply invokes the XRE. The contents of the .moz files, for example, correspond to the initialization parameters passed to xre_main.

Is this Mozilla's counter to XAML?

> Is this Mozilla's counter to XAML?

Depends on how you look at it ;-)

It seems to me that MS is simply catching on to the fact that XML based languages for describing UI (XUL) and bindings (XBL) are a "good thing."

With XULRunner, we are trying to make it easier to build applications using XUL, XBL, and XPCOM. Folks have already been doing this (e.g., ActiveState IDE); however, currently one needs to write at least some C++ code to do so.

XULRunner is about making it as easy to create rich, cross-platform XUL applications as it is to create rich, cross-platform XUL extensions for Firefox today.

WOW!!!! This is ***the*** thing. I can't wait.

Sorry, I can't find the XULRUNNER_20040804_BRANCH on cvs.mozilla.org :/
I use TortoiseCVS on Windows.

My apologies, I launched cvs.exe in command line mod and it works. Thanks :)