diff --git a/src/config-schema.coffee b/src/config-schema.coffee
index 54a3f11ad..b0b7a950a 100644
--- a/src/config-schema.coffee
+++ b/src/config-schema.coffee
@@ -7,6 +7,13 @@ module.exports =
   core:
     type: 'object'
     properties:
+      workspace:
+        type: 'object'
+        properties:
+          mode:
+            type: 'string'
+            default: 'list'
+            enum: ['split', 'list']
       showUnreadBadge:
         type: 'boolean'
         default: true