Last.fm plugin buggie [#5271]

[Fraxav]

I noticed that a subpanel of the plugin causes the option panel to lose its 'on top' position and MM isn't accesible until you find the panel again, that is pretty difficoult.
You can reproduce like this:
- Start MM
- Open a couple of computer folders and your browser
- Now, in MM, go to Options, General plugins. Select 'Last.fm scrobbler' and click Configure. A message will appear and you have to click NO (that make no sense, to me...whatever). Now if you try to click on the MM window nothing happens because the options panel is 'hidden' somewhere and you need to bring it on top.
Other subpanels in MM seem to work fine so I thought it's about the plugin...