Many times I have noticed Firefox spends quite a while "looking up" stuff when on the same system other programs are a lot faster to resolve.
Now I think I have found the culprit, actually Manu has found it:
Firefox seems to mantain its own DNS cache which apparently, contrary to its purpose, can slow things down if your ISP provides fast resolving server or if you run your own locally.
Anyway, this is the case for me so I followed Manu's advice and disabled DNS caching in Firefox and as a result average browsing experience does seem faster. How about that ...
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