diff --git a/lib/core/option.py b/lib/core/option.py
index 137176323..4183dcf89 100644
--- a/lib/core/option.py
+++ b/lib/core/option.py
@@ -1200,7 +1200,7 @@ def _setHTTPExtraHeaders():
         conf.headers = conf.headers.split("\n") if "\n" in conf.headers else conf.headers.split("\\n")
 
         for headerValue in conf.headers:
-            if headerValue.count(':') > 1:
+            if headerValue.count(':') >= 1:
                 header, value = (_.lstrip() for _ in headerValue.split(":", 1))
 
                 if header and value: