diff --git a/assets/syntaxes/Manpage.sublime-syntax b/assets/syntaxes/Manpage.sublime-syntax
index ceec32526a..e99c24974d 100644
--- a/assets/syntaxes/Manpage.sublime-syntax
+++ b/assets/syntaxes/Manpage.sublime-syntax
@@ -36,9 +36,18 @@ contexts:
     - match: '^\S.*$'
       scope: markup.heading
 
-    - match: '\b([a-z0-9_\-]+)(\()([^)]*)(\))'
+    - match: '\b([A-Za-z0-9_\-]+)(\()([^)]*)(\))'
       captures:
         1: entity.name.function
         2: keyword.operator
         3: constant.numeric
         4: keyword.operator
+
+    # command-line options like --option=value, --some-flag, or -x
+    - match: '(?:[^a-zA-Z0-9_-]|^|\s)(--?[A-Za-z0-9][A-Za-z0-9-]*)(?:(=)?("?)([A-Za-z0-9]+)("?))?'
+      captures:
+        1: entity.name
+        2: keyword.operator
+        3: punctuation.definition.string.begin
+        4: variable.parameter
+        3: punctuation.definition.string.end