Fixed downloading images with complex content-type header

boards/forms.py

@@ -251,7 +251,7 b' class PostForm(NeboardForm):'
         try:
             # Verify content headers
             response_head = requests.head(url, verify=False)
-            content_type = response_head.headers['content-type']
+            content_type = response_head.headers['content-type'].split(';')[0]
             if content_type in CONTENT_TYPE_IMAGE:
                 length_header = response_head.headers.get('content-length')
                 if length_header: