I don't know why this doesn't happen on our CI but it does happen for me locally.

It might also make sense to move that pref to a global place where it's set for all prefs. Otherwise other tests will probably just start failing whenever new tests are added.

Comment on attachment 8442105 [details] [diff] [review] 0001-Bug-1027084-Disable-about-home-snippets-when-running.patch Review of attachment 8442105 [details] [diff] [review]: ----------------------------------------------------------------- How is this test loading about:home? I thought we had removed it from most of the tests

I have no clue. Something must be loading snippets, I don't know what exactly.

Yeah, about:home is actually getting loaded but I don't know why :) Doesn't happen when I run only this single test but happens always when I run the whole test suite.

about:home is the default page that is loaded when opening new windows. We should change sessionstore tests to explicitly open new windows with about:blank as the start page.

sorry had to backout for bc1 - testbustage like https://tbpl.mozilla.org/php/getParsedLog.php?id=42612119&tree=Fx-Team

I totally missed that the failing test behaves differently on OSX and runs a different set of tests, how evil.

Pushed again with a small fix for non-OSX platforms: https://hg.mozilla.org/integration/fx-team/rev/6b8f91ea1013