bug: Preferences not loaded from config file

[azurit]

Some of the preferences are NOT loaded back from config file, for example $conf[server][server_list]. How to reproduce:

• Set $conf[server][server_list] via GUI (Administration - Configuration) to Shown.
• Save configuration.
• Observe that $conf[server][server_list] remained to None in GUI but was correctly saved into config as shown.

[azurit]

I noticed the same behavior with multiple preferences (but not all).

Looks like it's related to all preferences at least in IMP.