diff --git a/test/test_composer_blueprint_registered.py b/test/test_composer_blueprint_registered.py
new file mode 100644
index 00000000..2b56caac
--- /dev/null
+++ b/test/test_composer_blueprint_registered.py
@@ -0,0 +1,64 @@
+"""composer_bp must actually be registered on the Flask app.
+
+web_interface/blueprints/composer.py defines a full blueprint -- the
+/composer/ page, /composer/api/generate, /composer/api/install, etc. -- but
+nothing in web_interface/app.py imported or registered it. pages_v3 and
+api_v3 both go through the same "import, wire managers, register_blueprint"
+sequence; composer_bp had none of the three. The routes existed and worked
+in isolation (every other composer test builds its own minimal Flask app
+and registers composer_bp directly), but in the real running app every
+composer URL -- including the page itself -- was a 404, and the frontend's
+hardcoded '/composer/api/...' fetches (composer-app.js) had nothing to
+reach.
+
+app.py has import-time side effects (it loads config, builds managers, and
+in some configurations starts background threads), so this scans the source
+text rather than importing the module -- the same approach already used for
+test_composer_js_contracts.py's structural checks.
+"""
+import re
+from pathlib import Path
+
+APP_PY = Path(__file__).resolve().parent.parent / "web_interface" / "app.py"
+
+
+def _source() -> str:
+    return APP_PY.read_text()
+
+
+def test_composer_blueprint_is_imported():
+    src = _source()
+    assert re.search(
+        r"from web_interface\.blueprints\.composer import composer_bp", src
+    ), "app.py never imports composer_bp"
+
+
+def test_composer_blueprint_is_registered_under_composer_prefix():
+    src = _source()
+    match = re.search(
+        r"app\.register_blueprint\(\s*composer_bp\s*,\s*url_prefix\s*=\s*"
+        r"['\"](?P<prefix>[^'\"]*)['\"]",
+        src,
+    )
+    assert match, "app.py never calls app.register_blueprint(composer_bp, ...)"
+    # composer.html and composer-app.js hardcode '/composer/api/...' and
+    # '/composer/api/fonts/...' -- any other prefix serves a page whose own
+    # fetches and @font-face all 404.
+    assert match.group("prefix") == "/composer"
+
+
+def test_composer_blueprint_managers_are_wired_before_registration():
+    """Registered with no managers set means every route 503s or crashes.
+
+    composer.py initialises config_manager/plugin_manager/plugins_dir/
+    project_root to None at import time specifically so app.py can set them
+    -- the same pattern api_v3 and pages_v3 use.
+    """
+    src = _source()
+    register_match = re.search(r"app\.register_blueprint\(\s*composer_bp", src)
+    assert register_match, "app.py never registers composer_bp"
+    before_registration = src[: register_match.start()]
+    for attr in ("config_manager", "plugin_manager", "plugins_dir", "project_root"):
+        assert re.search(rf"composer_bp\.{attr}\s*=", before_registration), (
+            f"composer_bp.{attr} is never set before registration"
+        )
diff --git a/test/test_composer_empty_block.py b/test/test_composer_empty_block.py
index 954d391b..296db78f 100644
--- a/test/test_composer_empty_block.py
+++ b/test/test_composer_empty_block.py
@@ -78,3 +78,24 @@ def test_template_closes_the_branch_chain_with_a_fallback():
     text = TEMPLATE.read_text()
     assert "{% else %}" in text
     assert "pass  # element type" in text
+
+
+@pytest.mark.parametrize("wrapper", [
+    {"minWidth": 64},
+    {"blink": True},
+    {"minWidth": 64, "blink": True},
+])
+def test_dynamic_text_with_non_config_binding_does_not_break_generation(wrapper):
+    """dynamic_text only renders a body for binding.source == 'config'.
+
+    _preprocess_elements accepts any string as binding.source (it just
+    defaults a missing one to 'config'), so a 'live' or 'sensor' source --
+    anything a client sends that isn't literally 'config' -- hit the same
+    empty-if-block bug as an undrawable element type, just one level deeper:
+    the branch is taken, but its own inner `if` produced nothing.
+    """
+    element = {"type": "dynamic_text", "x": 0, "y": 0, "color": "#ffffff",
+               "binding": {"source": "live", "key": "temperature"}, **wrapper}
+    files = generate(element)          # must not raise ComposerInputError
+    assert "manager.py" in files
+    assert 'binding_source "live" draws nothing' in files["manager.py"]
diff --git a/web_interface/app.py b/web_interface/app.py
index 98bf0f71..3adc2402 100644
--- a/web_interface/app.py
+++ b/web_interface/app.py
@@ -157,6 +157,7 @@ _health_monitor_initialized = False
 # Register blueprints
 from web_interface.blueprints.pages_v3 import pages_v3
 from web_interface.blueprints.api_v3 import api_v3
+from web_interface.blueprints.composer import composer_bp
 
 # Initialize managers in blueprints
 pages_v3.config_manager = config_manager
@@ -173,6 +174,11 @@ api_v3.operation_queue = operation_queue
 api_v3.plugin_state_manager = plugin_state_manager
 api_v3.operation_history = operation_history
 api_v3.health_monitor = health_monitor
+
+composer_bp.config_manager = config_manager
+composer_bp.plugin_manager = plugin_manager
+composer_bp.plugins_dir = plugins_dir
+composer_bp.project_root = project_root
 # Initialize cache manager for API endpoints
 from src.cache_manager import CacheManager
 api_v3.cache_manager = CacheManager()
@@ -200,6 +206,7 @@ except Exception as _hm_err:  # pragma: no cover - defensive startup guard
 app.register_blueprint(pages_v3, url_prefix='')
 app.register_blueprint(pages_v3, url_prefix='/v3', name='pages_v3_legacy')
 app.register_blueprint(api_v3, url_prefix='/api/v3')
+app.register_blueprint(composer_bp, url_prefix='/composer')
 
 # Route to serve plugin asset files (registered on main app, not blueprint, for /assets/... path)
 @app.route('/assets/plugins/<plugin_id>/uploads/<path:filename>', methods=['GET'])
diff --git a/web_interface/templates/v3/composer/manager.py.j2 b/web_interface/templates/v3/composer/manager.py.j2
index 87d9fa9a..c4ff2541 100644
--- a/web_interface/templates/v3/composer/manager.py.j2
+++ b/web_interface/templates/v3/composer/manager.py.j2
@@ -110,6 +110,8 @@ class {{ class_name }}(BasePlugin):
 {{ pi }}    color={{ el.rgb_tuple }},
 {{ pi }}    font=self.display_manager.{{ el.font_attr }},
 {{ pi }})
+{% else %}
+{{ pi }}pass  # dynamic_text binding_source "{{ el.binding_source }}" draws nothing
 {% endif %}
 {% elif el.type == 'clock' %}
 {{ pi }}self.display_manager.draw_text(