we can probably slightly improve the post-filtering of duplicate entries by also using the finalcomplete value of the autoFill entry and maybe trying to strip www.
This is still an issue with current unified autocomplete implementation.
Any news on this ?
I'm glad to say that Firefox 53 greatly improved deduplication.
yes, the second part of this has been handled in bug 1322747. We could still investigate merging www. and non-www. entries, but that's not a priority atm, I think the most problematic part has been handled. So, I'm dropping this since I'm overloaded already and doubt I can fix this anytime soon. Patches with tests are welcome though!