I would strongly resist that because you are making a rod for
your own back for no useful purpose whatever.
You have to manually change each topic file name within
Project Manager and make sure you specify the extension for the
start page when you generate. I think that will ensure all files
are HTML but check it out. Also check out that everything works as
whilst that will give the right file extension, I haven't tested
search, index, glossary etc.
Also bear in mind there is no way to make RH create new files
with that extension. You have to remember to do it manually
yourself.
Unless the developers can come up with a very persuasive why,
which does not include "because we are the developers", a
suggestion that they do a foxtrot with Oscar might be appropriate.
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