Sorry, I haven't seen a feature like that in the Firefox 5.0 betas, and the acceptance of new features is done for 5.0. I haven't seen a feature like that mentioned for Firefox 6.0 or 7.0 either, but both of those pre-release versions are still receiving new features, as they are both in the alpha stage.

If you download the theme (right click and Save Link As) and install it locally by opening the XPI file via File > Open File then you already have the file.
A .JAR file needs to be dragged in the Theme Manager window (Tools > Add-ons > Appearance/Themes)

Hi cor-el. What I'm looking for in Firefox is what I use for IE8. I have windowsblind for changing the look of the toolbars in IE8 at startup. Don't want the same look that IE8 has, in Firefox. Firefox has the personas able to change automatically. Was looking for that in the themes. I know in the themes I can "add to collection", but I will not give any one my password to my emails. Thanks anyway. It's really no big thing to have to do a click or two more to get another look once a week or so.

Well cor-el, I have to eat crow. Did a little more digging and you are right. Firefox 4 has a different look when I click tools- add-on then what I remember from the others Firefox browser. So my saved theme list is there, but would still like it to be changed automatically. Think there be any chance of that in the future? So mark this solved. Thanks again for the headsup. Frank