User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Firefox/60.0 Build ID: 20180225220119 Steps to reproduce: Download the en-US locale nightly and a language pack (e.g. zh-CN). Install them. Set intl.locale.requested pref correspondingly and restart. Actual results: Only some of the browser are translated. Other don't. Untranslated things include: * context menu in webpages (except for the "Search ... with" item) * the urlbar * context menu of the tabline * context menu of the tabs (except for the "Mute tab" item) * the main menu Translated things include: * the about:addons page * context menu of the urlbar (text part) * things from extensions * about:preferences except the left navigation column * and some items in other menus Expected results: Most things should be translated after enabling the language pack and setting the correct locale. It happens only recently. mozregression-gui doesn't work well with language packs so I don't exactly when.

User-Agent Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:60.0) Gecko/20100101 Firefox/60.0 Build-ID 20180301024724 I was able to reproduce this issue on the latest Nightly build using Windows 10 x64. Narrowed inbound regression window from [dbd1c8bc, f0a6945b] (4 builds) to [cb9d2116, f0a6945b] (2 builds) (~1 steps left) No more inbound revisions, bisection finished. Last good revision: cb9d2116b32d9242c3b6cce4caf7df3dae82e7a1 First bad revision: f0a6945be22cbff36c06c85fbf88579663565d36 Pushlog: https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=cb9d2116b32d9242c3b6cce4caf7df3dae82e7a1&tochange=f0a6945be22cbff36c06c85fbf88579663565d36 It looks like bug 1431260 has caused this. Gandalf, could you please take a look at this?

Thanks for reporting! It's been also reported as bug 1441135 and I got a fix landed there! Should be fixed by today's nightly.