Launch "reduce whitespace" feature

Fixed: twpowertools:130
Change-Id: I4d5f7d9b49338a9eeaea837f7a4ef574161550aa
diff --git a/src/options/optionsPage.json5 b/src/options/optionsPage.json5
index a5c9ff5..1b4f4d3 100644
--- a/src/options/optionsPage.json5
+++ b/src/options/optionsPage.json5
@@ -44,6 +44,7 @@
         {codename: 'repositionexpandthread', experimental: true},
         {codename: 'imagemaxheight'},
         {codename: 'interopthreadpage'},
+        {codename: 'uispacing'},
       ],
     },
   ],