Closes #7531: Add Markdown support for strikethrough formatting

netbox/utilities/markdown.py

@@ -0,0 +1,16 @@
+import markdown
+from markdown.inlinepatterns import SimpleTagPattern
+
+STRIKE_RE = r'(~{2})(.+?)(~{2})'
+
+
+class StrikethroughExtension(markdown.Extension):
+    """
+    A python-markdown extension which support strikethrough formatting (e.g. "~~text~~").
+    """
+    def extendMarkdown(self, md):
+        md.inlinePatterns.register(
+            markdown.inlinepatterns.SimpleTagPattern(STRIKE_RE, 'del'),
+            'strikethrough',
+            200
+        )