Firefox will leave registry entries for your favorites, etc. This from the Firefox page:
Note: Do not unzip Firefox to a directory that already contains a previous version of Firefox. Either delete the existing directory, move it out of the way or create a new directory. If you install Firefox on top of an existing Firefox or Mozilla directory you will have problems.
http://texturizer.net/firefox/download.html#install
But I'd back up everything just in case.
If I download the new Mozilla Firefox 0.9, do I let it over write the previous version 0.8, or do I have to uninstall it first ? I would like to save/transfer my settings and bookmarks to the new version.
Thanks.
christy

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