The fix in bug 1658646 made search mode a bit more confusing, in particular the history search doesn't seem to be restricted to the alias domain.
I just tried to search for a short string while search mode was enabled on Wikipedia, I got 2 history results from www.google.com where my typed string was matching the query string. Those were completely unexpected since I'm trying to focus on Wikipedia results.

It sounds like we missed a piece due to testing on non-chaotic enough profiles, I think the results should only come from pages with the alias domain, not others? That could be matter of modifying the search string for the history search to include that domain.

Did you see this on a Nightly with bug 1659775 applied?

(In reply to Harry Twyford [:harry] from comment #1)

Did you see this on a Nightly with bug 1659775 applied?

yep, in today's Nightly.
Actually I see what it is, it is addresses like "https://www.google.com/url?...wikipedia..." that match on the domain. I think any url containing another url will cause this. Basically the search is correct but it's not really limiting the search to a specific host.

Ah I see. Yeah, that makes sense.

(In reply to Marco Bonardo [:mak] from comment #0)

That could be matter of modifying the search string for the history search to include that domain.

That's what bug 1658646 does (or it supposed to do). It adds the engine's host to the _keywordSubstitutedSearchString. So in Wikipedia search mode, we're just executing a search for <locale>.wikipedia.org <query>, which would let Google URLs containing Wikipedia URLs through...

(In reply to Harry Twyford [:harry] from comment #3)

So in Wikipedia search mode, we're just executing a search for <locale>.wikipedia.org <query>, which would let Google URLs containing Wikipedia URLs through...

yes, and it's not just google urls, a lot of other services have urls into their urls... maybe we need a post-facto filter checking the host and dropping unwanted results, or we'd need to modify UnifiedComplete to support filtering on host (this would be a lot more efficient).

I'll check how complex it would be to search only specific hosts in UnifiedComplete.

https://hg.mozilla.org/mozilla-central/rev/3346ff1d921f