diff --git a/package.json b/package.json
index 6c0cd4254..250d0ecdd 100644
--- a/package.json
+++ b/package.json
@@ -23,7 +23,7 @@
     "color": "^0.7.3",
     "event-kit": "^1.3.0",
     "find-parent-dir": "^0.3.0",
-    "first-mate": "^5.0.0",
+    "first-mate": "^5.1.0",
     "fs-plus": "^2.8.0",
     "fstream": "0.1.24",
     "fuzzaldrin": "^2.1",
diff --git a/spec/spec-helper.coffee b/spec/spec-helper.coffee
index c659a6954..7ed77bc2a 100644
--- a/spec/spec-helper.coffee
+++ b/spec/spec-helper.coffee
@@ -69,7 +69,6 @@ beforeEach ->
   spyOn(window, "clearTimeout").andCallFake window.fakeClearTimeout
 
   spyOn(atom, 'saveStateSync')
-  atom.grammars.clearGrammarOverrides()
 
   spyOn(atom.packages, 'resolvePackagePath').andCallThrough()
 
diff --git a/src/atom-environment.coffee b/src/atom-environment.coffee
index d8b8ed754..de410ef23 100644
--- a/src/atom-environment.coffee
+++ b/src/atom-environment.coffee
@@ -246,6 +246,8 @@ class AtomEnvironment extends Model
     @commands.clear()
     @registerDefaultCommands()
 
+    @grammars.clear()
+
     @styles.restoreSnapshot(params?.stylesSnapshot ? [])
 
     @menu.clear()
diff --git a/src/grammar-registry.coffee b/src/grammar-registry.coffee
index 65d6b1731..4a5352275 100644
--- a/src/grammar-registry.coffee
+++ b/src/grammar-registry.coffee
@@ -123,6 +123,3 @@ class GrammarRegistry extends FirstMate.GrammarRegistry
   clearGrammarOverrides: ->
     @grammarOverridesByPath = {}
     undefined
-
-  clearObservers: ->
-    @emitter = new Emitter