diff --git a/internal_packages/inbox-light-ui/stylesheets/panels.less b/internal_packages/inbox-light-ui/stylesheets/panels.less
index a64edad88..744c3e2a5 100644
--- a/internal_packages/inbox-light-ui/stylesheets/panels.less
+++ b/internal_packages/inbox-light-ui/stylesheets/panels.less
@@ -35,7 +35,7 @@ atom-workspace {
 
   #thread-list-column {
     order: 1;
-    flex: 1.5;
+    flex: 1.2;
     min-width: 320px;
     overflow: auto;
     flex-direction: column;
@@ -43,7 +43,7 @@ atom-workspace {
 
   #message-and-composer {
     order: 3;
-    min-width: 580px;
+    min-width: 600px;
     max-width: 1024px;
     position: relative;
     background: @background-color-secondary;