How to delete/map Activities?

[Petrus de Calguarium]

Anne Wilson wrote:

> I understand that in 4.4 (not yet released) this 
problem doesn't occur.

You answered with what I already knew, of course. 
Growing pains. This is simply a bug that has not been 
fixed yet.

I do like the 4 different activities on 4 desktops, as 
it finally, after 10 years of fedora/redhat, actually 
makes having virtual desktops useful to me (I usually 
close programs when I have finished using them, so it 
is rare that I have more than 3 open at a time and it 
is rare that I need to move one to another desktop).

I will likely continue to use this feature, despite 
the glitch, as it is not totally unusable.

Do plasmoids on activities that are not being used eat 
up cpu capacity?