[Plugin: W3 Total Cache] "Save" button does not appear on tab pages

The css float on p.submit seems to be causing this. As a fast solution you can start chrome inspector or firebug, and disable the float on the element. The save button will become visible.

Have to ask: have you cleared your browser cache?

same problem to me and there is not solution

Which OS, browser & version etc are you using?

I would imagine this is an old version of W3TC.