This problem only appears on certain keyboards and languages where left and right square brackets are placed on letters F and G. Even if you have similar problem with different keyboard or key binding /letters you can still use this solution.
I was using Sublime Text 2, which is really fantastic editor, on Windows
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When you want to install or upgrade a plugin, WordPress will most probably display this message:
Connection Information
To perform the requested action, WordPress needs to access your web server. Please enter your FTP credentials to proceed. If you do not remember your credentials, you should contact your web host.
If you are on shared
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