indirect-region (make-indirect-buffer) breaks major-mode fontification

[senny]

Hey there

I am looking for a way to edit java-script and css snippets in a HTML
document with their corresponding major modes. I've tried some of the
multi major mode solutions but found most of them buggy and performing
slowly. Recently I found the indirect-buffer feature of emacs. This is
exactly what I am looking for but it somehow breaks fontification.
When I clone a region into an indirect buffer the code does not get
highlighted correctly.

This seems only to happen when the original buffer is visible in an
other window. when I only edit the indirect buffer, then fontification
works as expected.

Is there a workaround for this problem?

Regards,
Senny