diff --git a/docs/conf.py b/docs/conf.py
index 1a465806e..52f603568 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -84,12 +84,12 @@ def __getattr__(self, name):
 
     warnings.filterwarnings(
         "ignore",
-        message=r"The rc setting 'colorbar.rasterize' was deprecated.*",
         category=UltraPlotWarning,
     )
 except Exception:
     pass
 
+
 # Print available system fonts
 from matplotlib.font_manager import fontManager
 from sphinx_gallery.sorting import ExplicitOrder, FileNameSortKey
@@ -349,6 +349,9 @@ def _reset_ultraplot(gallery_conf, fname):
 
 nbsphinx_execute = "auto"
 
+# Suppress warnings in nbsphinx kernels without injecting visible cells.
+os.environ.setdefault("PYTHONWARNINGS", "ignore::UserWarning")
+
 # Sphinx gallery configuration
 sphinx_gallery_conf = {
     "doc_module": ("ultraplot",),