diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 9d319c9a..60015865 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -34,7 +34,7 @@ repos:
     rev: v0.6.7
     hooks:
       - id: ruff
-        args: [--fix]
+        args: [--fix, '--extend-exclude', '*.ipynb']
   - repo: https://github.com/pre-commit/mirrors-mypy
     rev: v1.11.2
     hooks:
diff --git a/src/duqtools/dashboard/_shared.py b/src/duqtools/dashboard/_shared.py
index b1dc5ccb..77c35982 100644
--- a/src/duqtools/dashboard/_shared.py
+++ b/src/duqtools/dashboard/_shared.py
@@ -106,20 +106,25 @@ def get_base64_of_bin_file(png_file):
 
 
 def build_markup_for_logo(
-    png_file,
-    background_position='50% 10%',
-    margin_top='10%',
-    image_width='60%',
-    image_height='',
+        png_file,
+        background_position='50% 10%',
+        margin_top='10%',
+        image_width='53%',
+        image_height='100%',
+        nav=True,  # page has navigation
 ):
     binary_string = get_base64_of_bin_file(png_file)
+
+    loc = 'stSidebarHeader' if nav else 'stSidebarUserContent'
+
     return f"""
             <style>
-                [data-testid="stSidebarNav"] {{
+                [data-testid="{loc}"] {{
                     background-image: url("data:image/png;base64,{binary_string}");
                     background-repeat: no-repeat;
                     background-position: {background_position};
                     margin-top: {margin_top};
+                    margin-bottom: {margin_top};
                     background-size: {image_width} {image_height};
                 }}
             </style>
@@ -129,7 +134,7 @@ def build_markup_for_logo(
 def add_sidebar_logo():
     """Based on: https://stackoverflow.com/a/73278825."""
     png_file = data_directory / 'logo.png'
-    logo_markup = build_markup_for_logo(png_file)
+    logo_markup = build_markup_for_logo(png_file, nav=True)
     st.markdown(
         logo_markup,
         unsafe_allow_html=True,
diff --git a/src/duqtools/schema/_dimensions.py b/src/duqtools/schema/_dimensions.py
index 0a0057a9..dc5dbcc7 100644
--- a/src/duqtools/schema/_dimensions.py
+++ b/src/duqtools/schema/_dimensions.py
@@ -105,7 +105,7 @@ def check_custom(cls, values):
         return values
 
     def _custom_function(self,
-                         data: np.ndarray,
+                         data: np.ndarray | float,
                          value,
                          *,
                          out: Optional[np.ndarray] = None,
@@ -125,6 +125,7 @@ def npfunc(self,
                out: Optional[np.ndarray] = None,
                var: Optional[Any] = None) -> Any:
         if self.operator == 'custom':
+            assert self.custom_code
             npfunc = partial(self._custom_function,
                              code=self.custom_code,
                              var=var)