Please leave the default installation directory empty. i.e. when a user installs Joomla!, is adds "joomla" as installation directory automatically, and if the user doesn't know better it gets installed into the "joomla" directory instead of the website root.
We have implemented this in 3.1
3.1 will be released in the next 7 days for sure.
----------------------- For immediate support please email us at our Support email address. PMs sent to any Softaculous Team member or posting in the forums is not the official way to get support.
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