10.10 desktop panel problem

[O. Sinclair]

Have an irritating problem with the plasma panel after installing 10.10

I frequently use an external monitor and when I connect to that (being 
larger than the laptop LCD) the panel does not automatically resize but 
keeps a fixed size at the bottom of the screen. Have to unlock widgets 
and resize panel every time.

Anyone knows if there is an "rc" file somewhere or if I missed a 
"automatically maximize panel" setting somewhere?

Kindly
Sinclair