diff --git a/tests/roots/test-root/conf.py b/tests/roots/test-root/conf.py
index 34cafa7671..687445a702 100644
--- a/tests/roots/test-root/conf.py
+++ b/tests/roots/test-root/conf.py
@@ -42,7 +42,7 @@
 coverage_c_path = ['special/*.h']
 coverage_c_regexes = {'function': r'^PyAPI_FUNC\(.*\)\s+([^_][\w_]+)'}
 
-extlinks = {'issue': ('http://bugs.python.org/issue%s', 'issue '),
+extlinks = {'issue': ('http://bugs.python.org/issue%s', 'issue %s'),
             'pyurl': ('http://python.org/%s', None)}
 
 # modify tags from conf.py