Lewis' Blog Tales from the trenches of information technology


Updating Firefox on Linux: the Dreaded “Couldn’t load XPCOM”

I bumped into this annoyance while updating my openSUSE 11.4 workstation tonight.

There are numerous mentions of this issue on the net, and numerous suggestions for addressing it. However, none of them (which I saw) really hits on the underlying problem, which is that somewhere, somehow, XPCOM can't start.

To understand what's going on, it's important to have a basic understanding of what XPCOM is, and how it is involved with Mozilla apps. XPCOM is an acronym for  "Cross Platform Component Object Model," which is Mozilla's equivalent technology to CORBA or Microsoft's COM. Like any other "object model," XPCOM's function is to provide a modular framework vs a monolithic one. This modularization allows XPCOM to be (mostly) platform-neutral, making it possible to run the Gecko rendering engine on a variety of platforms. So, as the Gecko engine is composed of XPCOM components, if XPCOM cannot start, Gecko cannot start. If Gecko cannot start, then there is no rendering engine for the application, essentially stopping whichever Mozilla-based app one might wish to run, before it even gets started.