Comment 25 for bug 30791

As I said on IRC, here is my theory:

> This file is a registry of components including extensions.
> If you have pre-1.4.99 extensions installed then this compreg.dat file is
updated by those extensions somehow, normally.
> But the 1.0.7 package makes it a symlink to /var so the file ends up in /var.
> Now the 1.5 package removes the symlink. Then if anything were to try to
create the file in /usr it would just go ahead and do so.
...
> The problem is obviously that something is creating it again later.
> And it has to be something than runs as root.
> So my best guess at the culprit is some extension or embedder's maintainer
scripts, probably indirectly.

> How about this for a plan: since we have a workaround (delete the file) I will
postpone dealing with this until my next round of firefox maintenance (ie
probably at least a week). In the meantime if any information surfaces about
what creates the file we can add it to the bug report.

> I'll change the bug priority to P1 to make sure I pick it up later.