diff --git a/src/browser/base/content/zen-styles/zen-decks.css b/src/browser/base/content/zen-styles/zen-decks.css
index 4c473c8a7..88e9ae436 100644
--- a/src/browser/base/content/zen-styles/zen-decks.css
+++ b/src/browser/base/content/zen-styles/zen-decks.css
@@ -37,6 +37,9 @@
 
 #tabbrowser-tabpanels[zen-split-view='true']:not([zen-split-resizing]) > [zen-split-anim='true'] {
   transition: inset 0.08s ease-out;
+  & browser {
+    transition: opacity 0.2s ease-out;
+  }
 }
 
 #tabbrowser-tabpanels[zen-split-view='true'] .browserSidebarContainer.deck-selected {