add opacity to all scatter traces

Author: nicolaskruchten

plotly_express/_chart_types.py

@@ -723,6 +723,7 @@ def scatter_geo(
     color_discrete_map={},
     color_continuous_scale=None,
     color_continuous_midpoint=None,
+    opacity=None,
     size_max=None,
     projection=None,
     scope=None,
@@ -803,6 +804,7 @@ def scatter_mapbox(
     color_discrete_map={},
     color_continuous_scale=None,
     color_continuous_midpoint=None,
+    opacity=None,
     size_max=None,
     zoom=8,
     title=None,