Where have plug-ins gone ?

Ever since I received a message yesterday about a plug-in that is not supported by the current version of Lightroom my plug-in pane has disappeared.

I do not mean that individual plug-ins are missing, I mean the whole pane has gone, and it is not listed in the options on right-clicking in the bar. Presets, Snapshots etc are shown, but not plugins.

Interestingly enough, the plug-in manager shows everything installed and running.

Any ideas.

BTW - am I missing something, or has Adobe carefully arranged support so that there is no way to gain assistance other than through the fantastic efforts of the participants in these forums ?