diff --git a/kitty/window.py b/kitty/window.py
index e2cf564af..a80741d2e 100644
--- a/kitty/window.py
+++ b/kitty/window.py
@@ -213,8 +213,9 @@ def compile_match_query(exp: str, is_simple: bool = True) -> MatchPatternType:
 def decode_cmdline(x: str) -> str:
     ctype, sep, val = x.partition('=')
     if ctype == 'cmdline':
-        return next(shlex_split(val, True))
-    if ctype == 'cmdline_url':
+        with suppress(StopIteration):
+            return next(shlex_split(val, True))
+    elif ctype == 'cmdline_url':
         from urllib.parse import unquote
         return unquote(val)
     return ''