diff --git a/app/assets/javascripts/diffs/store/actions.js b/app/assets/javascripts/diffs/store/actions.js
index e5bb9904664..27001142257 100644
--- a/app/assets/javascripts/diffs/store/actions.js
+++ b/app/assets/javascripts/diffs/store/actions.js
@@ -103,9 +103,7 @@ export const toggleFileDiscussions = ({ getters, dispatch }, diff) => {
 
     if (shouldCloseAll) {
       dispatch('collapseDiscussion', data, { root: true });
-    } else if (shouldExpandAll) {
-      dispatch('expandDiscussion', data, { root: true });
-    } else if (!shouldCloseAll && !shouldExpandAll && !discussion.expanded) {
+    } else if (shouldExpandAll || (!shouldCloseAll && !shouldExpandAll && !discussion.expanded)) {
       dispatch('expandDiscussion', data, { root: true });
     }
   });
diff --git a/spec/javascripts/diffs/store/actions_spec.js b/spec/javascripts/diffs/store/actions_spec.js
index 6829c1e956a..c1560dac1a0 100644
--- a/spec/javascripts/diffs/store/actions_spec.js
+++ b/spec/javascripts/diffs/store/actions_spec.js
@@ -191,4 +191,48 @@ describe('DiffsStoreActions', () => {
       );
     });
   });
+
+  describe('toggleFileDiscussions', () => {
+    it('should dispatch collapseDiscussion when all discussions are expanded', () => {
+      const getters = {
+        getDiffFileDiscussions: jasmine.createSpy().and.returnValue([{ id: 1 }]),
+        diffHasAllExpandedDiscussions: jasmine.createSpy().and.returnValue(true),
+        diffHasAllCollpasedDiscussions: jasmine.createSpy().and.returnValue(false),
+      };
+
+      const dispatch = jasmine.createSpy('dispatch');
+
+      actions.toggleFileDiscussions({ getters, dispatch });
+
+      expect(dispatch).toHaveBeenCalledWith('collapseDiscussion', { discussionId: 1 }, { root: true });
+    });
+
+    it('should dispatch expandDiscussion when all discussions are collapsed', () => {
+      const getters = {
+        getDiffFileDiscussions: jasmine.createSpy().and.returnValue([{ id: 1 }]),
+        diffHasAllExpandedDiscussions: jasmine.createSpy().and.returnValue(false),
+        diffHasAllCollpasedDiscussions: jasmine.createSpy().and.returnValue(true),
+      };
+
+      const dispatch = jasmine.createSpy();
+
+      actions.toggleFileDiscussions({ getters, dispatch });
+
+      expect(dispatch).toHaveBeenCalledWith('expandDiscussion', { discussionId: 1 }, { root: true });
+    });
+
+    it('should dispatch expandDiscussion when some discussions are collapsed and others are expanded for the collapsed discussion', () => {
+      const getters = {
+        getDiffFileDiscussions: jasmine.createSpy().and.returnValue([{ expanded: false, id: 1 }]),
+        diffHasAllExpandedDiscussions: jasmine.createSpy().and.returnValue(false),
+        diffHasAllCollpasedDiscussions: jasmine.createSpy().and.returnValue(false),
+      };
+
+      const dispatch = jasmine.createSpy();
+
+      actions.toggleFileDiscussions({ getters, dispatch });
+
+      expect(dispatch).toHaveBeenCalledWith('expandDiscussion', { discussionId: 1 }, { root: true });
+    });
+  });
 });