diff --git a/native/pages/blocks.py b/native/pages/blocks.py
index fe89e900..48a2c90a 100644
--- a/native/pages/blocks.py
+++ b/native/pages/blocks.py
@@ -61,6 +61,11 @@ def section(prefix: str, title: str, description: str, blocks):
         "Area Charts",
         "Filled line charts for showing trends over time.",
     ),
+    (
+        "line_chart",
+        "Line Charts",
+        "Line charts for showing trends over time.",
+    ),
     (
         "bar_chart",
         "Bar Charts",
diff --git a/tests/test_blocks_page.py b/tests/test_blocks_page.py
new file mode 100644
index 00000000..efd5d5ef
--- /dev/null
+++ b/tests/test_blocks_page.py
@@ -0,0 +1,35 @@
+"""Regression guard for the /blocks showcase page (``native/pages/blocks.py``).
+
+``BLOCK_GROUPS`` is a hardcoded allowlist that drives which block categories
+are rendered on the showcase page. When a new block category is added under
+``native/lib/blocks/`` but the matching ``BLOCK_GROUPS`` entry is forgotten,
+the category is silently dropped from the page (no error, no missing-button
+warning). This test asserts the allowlist stays in sync with what is on disk
+so that drift is caught automatically — the original bug omitted ``line_chart``
+while four ``line_chart_*.py`` files existed on disk.
+"""
+
+from __future__ import annotations
+
+import re
+
+from native.pages import blocks
+
+
+def _disk_prefixes():
+    """Block prefixes discoverable on disk, matching the loader's
+    ``<prefix>_<digits>.py`` naming convention (excludes ``__init__.py``)."""
+    prefixes = set()
+    pattern = re.compile(r"^([a-z_]+)_(\d+)\.py$")
+    for path in blocks.BLOCKS_PATH.glob("*.py"):
+        match = pattern.match(path.name)
+        if match:
+            prefixes.add(match.group(1))
+    return prefixes
+
+
+def test_block_groups_match_block_prefixes_on_disk():
+    """Every block prefix present on disk must be declared in
+    ``BLOCK_GROUPS`` (and vice versa) so every block category is rendered on
+    the showcase page."""
+    assert _disk_prefixes() == {group[0] for group in blocks.BLOCK_GROUPS}