diff --git a/setup/multitail.py b/setup/multitail.py
index 970f633711..cf4e8f30b6 100644
--- a/setup/multitail.py
+++ b/setup/multitail.py
@@ -48,10 +48,10 @@ def nonblocking_readlines(window, fileobj, buf, name, copy_to=None):
 
 def show_line(window, line, fname):
     line = clean_pat.sub(b'', line)
+    max_lines, max_chars = window.getmaxyx()
     if line:
         continue_prompt = b'> '
         title = str(b" %s " % fname)
-        max_lines, max_chars = window.getmaxyx()
         max_line_len = max_chars - 2
         if len(line) > max_line_len:
             first_portion = line[0:max_line_len - 1]