User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:48.0) Gecko/20100101 Firefox/48.0 Build ID: 20160817112116 Steps to reproduce: I added <textbox type="autocomplete" autocompletesearch="history"/> on a XUL page. Actual results: When I entered a short phrase in the box no suggestions appeared, although some history records with the phrase were existing. Expected results: Textbox should suggest history records if they are available and match entered phrase. I'm attaching a test addon, please install it and visit chrome://fftestaddon/content/test.xul, it's the page with the textbox. The addon works fine in Firefox 48, but not in 49.

https://hg.mozilla.org/integration/fx-team/pushloghtml?fromchange=738ec20418cc728910419aa60f98ae62b429facf&tochange=44a989cf6c1662b60e3113cb6503817b7fc31131 It's a consequence of bug 1223728. Marco, your thoughts about this case?

history search component is gone, the only supported search component is "unifiedcomplete". If you need help with that, feel free to ping me, but this is not a bug we plan to fix, the old component was just deprecated and removed.

ps: just as a side note, you can clearly write your own search component, as well as importing the old nsPlacesAutocomplete.js component into your add-on. This is the current search implementation, if you're looking for an example (quite complex actually for your purposes but may contain useful hints): http://searchfox.org/mozilla-central/source/toolkit/components/places/UnifiedComplete.js And this is the old component (that soon will be moved to comm-central repository and disappear from here): http://searchfox.org/mozilla-central/source/toolkit/components/places/nsPlacesAutoComplete.js

Marco, thank you for the useful information! I imported the old history autocomplete component and it seems it works fine for me.