In a clean fresh install of Firefox 3.0 (non portable) with no add-ons going to the following site works with no problem.
However, in a clean fresh install of Firefox 3.0 portable with no add-ons going to the same site returns the following error:
" The page you are trying to view cannot be shown because it uses an invalid or unsupported form of compression.
* Please contact the website owners to inform them of this problem. "
If I download the tiddly mentioned above, it works just fine locally in both installations of Firefox 3.0.
I have observed similar behavior in other tiddly based sites online, but not all.
Did you try Shift-F5 to reload the page without cache?
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