fix: pass through border-bottom for generated dropdown links

README.md

@@ -91,7 +91,7 @@ Each link in the `links` list supports:
 - `text` (string, required): The text displayed for the link
 - `url` (string, optional): The URL the link points to (not needed if using `submenu`)
 - `target` (string, optional): The target attribute (e.g., `_blank` for new tab)
-- `bottom-border` (bool or int, optional): Add bottom divider of width 1px if true, or given value in px if number
+- `border-bottom` (bool or int, optional): Add bottom divider of width 1px if true, or given value in px if number
 - `submenu` (list, optional): List of nested links for a submenu (see Nested Dropdowns below)
 
 ## Example: Using Shared Config File

USAGE.md

@@ -108,7 +108,7 @@ Each link in the `links` list supports:
 | `text` | string | Yes | The link text |
 | `url` | string | Conditional | The target URL (can be relative or absolute). Required unless `submenu` is provided. Optional when using `submenu` to make the parent clickable. |
 | `target` | string | No | HTML target attribute (e.g., `_blank` for new tab) |
-| `bottom-border` | bool or int | No | Add bottom divider of width 1px if true, or given value in px if number |
+| `border-bottom` | bool or int | No | Add bottom divider of width 1px if true, or given value in px if number |
 | `submenu` | list | No | List of nested links (creates a submenu). See Nested Dropdowns below. |
 
 ## Advanced Examples

mkdocs_header_dropdown/plugin.py

@@ -35,6 +35,11 @@ class HeaderDropdownPlugin(BasePlugin):
         ('dropdowns', config_options.Type(list, default=[])),
     )
 
+    _AUTO_GENERATED_LINK_METADATA_KEYS = {
+        'target',
+        'border-bottom',
+    }
+
     def _normalize_links(self, links):
         """
         Normalize `border-bottom` value. Default width is 1px if specified
@@ -60,6 +65,8 @@ def _normalize_links(self, links):
             if width>0:
                 style += f"border-bottom: {width}px solid var(--md-default-fg-color--lightest);"
             item['extra_style'] = style
+            if isinstance(item.get('submenu'), list):
+                item['submenu'] = self._normalize_links(item['submenu'])
             normalized.append(item)
         return normalized
 
@@ -84,11 +91,17 @@ def _generate_links_from_yaml(self, data, parent_key=None):
         if isinstance(data, dict):
             # Check for URL at this level
             parent_url = data.get('fallback') or data.get('url')
+            link_metadata = {
+                key: value
+                for key, value in data.items()
+                if key in self._AUTO_GENERATED_LINK_METADATA_KEYS
+            }
+            special_keys = {'fallback', 'url'} | self._AUTO_GENERATED_LINK_METADATA_KEYS
 
             # Collect submenu items from other keys
             submenu = []
             for key, value in data.items():
-                if key in ('fallback', 'url'):
+                if key in special_keys:
                     continue  # Skip these, used for parent URL
 
                 if isinstance(value, str):
@@ -103,7 +116,7 @@ def _generate_links_from_yaml(self, data, parent_key=None):
                     # Nested dict - flatten it one level up
                     # Don't create an intermediate item, just add its children directly
                     for nested_key, nested_value in value.items():
-                        if nested_key in ('fallback', 'url'):
+                        if nested_key in special_keys:
                             continue
                         if isinstance(nested_value, str):
                             # Format display name for era-specific docs
@@ -122,6 +135,7 @@ def _generate_links_from_yaml(self, data, parent_key=None):
                     'text': f"{parent_key}",
                     'target': '_blank'
                 }
+                link.update(link_metadata)
                 if parent_url:
                     link['url'] = parent_url
                 if submenu:

tests/test_plugin.py

@@ -0,0 +1,65 @@
+import unittest
+
+from mkdocs_header_dropdown.plugin import HeaderDropdownPlugin
+
+
+class AutoGeneratedLinksTest(unittest.TestCase):
+    def setUp(self):
+        self.plugin = HeaderDropdownPlugin()
+
+    def test_auto_generated_parent_preserves_link_metadata(self):
+        link = self.plugin._generate_links_from_yaml(
+            {
+                'fallback': 'https://example.com',
+                'target': '_self',
+                'border-bottom': True,
+            },
+            'Example',
+        )
+
+        self.assertEqual(
+            link,
+            {
+                'text': 'Example',
+                'target': '_self',
+                'border-bottom': True,
+                'url': 'https://example.com',
+            },
+        )
+
+    def test_auto_generated_metadata_keys_do_not_create_submenu_items(self):
+        link = self.plugin._generate_links_from_yaml(
+            {
+                'fallback': 'https://example.com',
+                'target': '_self',
+                'Run2': 'https://example.com/run2',
+            },
+            'Example',
+        )
+
+        self.assertEqual([item['text'] for item in link['submenu']], ['Run2'])
+
+    def test_normalize_links_handles_submenu_links(self):
+        links = [
+            {
+                'text': 'Parent',
+                'submenu': [
+                    {
+                        'text': 'Child',
+                        'url': 'https://example.com/child',
+                        'border-bottom': 2,
+                    }
+                ],
+            }
+        ]
+
+        normalized = self.plugin._normalize_links(links)
+
+        self.assertIn(
+            'border-bottom: 2px solid',
+            normalized[0]['submenu'][0]['extra_style'],
+        )
+
+
+if __name__ == '__main__':
+    unittest.main()