diff --git a/lib/turnsole/modes/thread-view-mode.rb b/lib/turnsole/modes/thread-view-mode.rb
index 318f4a4..6555283 100644
--- a/lib/turnsole/modes/thread-view-mode.rb
+++ b/lib/turnsole/modes/thread-view-mode.rb
@@ -491,6 +491,7 @@ def jump_to_next_and_open
     end
 
     nextm = @layouts[m].next
+    return unless nextm
     if @layouts[nextm].state == :closed
       @layouts[nextm].state = :open
       @layouts[nextm].toggled_state = true