What browser? I assume you've tried others?
Swiftfox. I've also tried Iceape, Opera and Epiphany. All show the same code change.
What does:
$ curl http://www2.foo.bar/baz.html
look like?
<link rev="x-refresh" href="" >
OK. So browser mangling is unlikely to be the problem.
I have set up a second virtual site on my computer so that I can use www2 instead of www because that's already used and I want to keep it separate.
This may be a red herring.
Ah! I suspected something fishy was going on.
You may, therefore, need to continue fishing in this pond.
Best, Richard