diff --git a/doc/python/interactive-html-export.md b/doc/python/interactive-html-export.md
index 013c87c286b..461afe7f548 100644
--- a/doc/python/interactive-html-export.md
+++ b/doc/python/interactive-html-export.md
@@ -64,6 +64,11 @@ You can insert Plotly output and text related to your data into HTML templates u
```
<!DOCTYPE html>
<html>
+<head>
+<meta charset="utf-8" /> <!--It is necessary to use the UTF-8 encoding with plotly graphics to get e.g. negative signs to render correctly -->
+<meta name="viewport" content="width=device-width, initial-scale=1.0" />
+</head>
+
<body>
<h1>Here's a Plotly graph!</h1>
{{ fig }}
diff --git a/doc/requirements.txt b/doc/requirements.txt
index 5c4ee639479..9d19b7b071a 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -21,6 +21,12 @@ squarify
scikit-image==0.18.1
scikit-learn
sphinx==3.5.4
+sphinxcontrib-applehelp==1.0.2
+sphinxcontrib-devhelp==1.0.2
+sphinxcontrib-htmlhelp==2.0.0
+sphinxcontrib-qthelp==1.0.3
+sphinxcontrib-serializinghtml==1.1.5
+sphinxcontrib-jsmath==1.0.1
sphinx_bootstrap_theme
recommonmark
pathlib
diff --git a/packages/python/plotly/plotly/express/_chart_types.py b/packages/python/plotly/plotly/express/_chart_types.py
index dc2b22599e5..74cdf84fa49 100644
--- a/packages/python/plotly/plotly/express/_chart_types.py
+++ b/packages/python/plotly/plotly/express/_chart_types.py
@@ -497,7 +497,7 @@ def histogram(
y=["If `orientation` is `'v'`, these values are used as inputs to `histfunc`."]
+ _wide_mode_xy_append,
histfunc=[
- "The arguments to this function are the values of `y`(`x`) if `orientation` is `'v'`(`'h'`).",
+ "The arguments to this function are the values of `y` (`x`) if `orientation` is `'v'` (`'h'`).",
],
),
)
diff --git a/packages/python/plotly/plotly/express/_doc.py b/packages/python/plotly/plotly/express/_doc.py
index 5137dea5b28..5a8690f856d 100644
--- a/packages/python/plotly/plotly/express/_doc.py
+++ b/packages/python/plotly/plotly/express/_doc.py
@@ -448,7 +448,7 @@
],
histfunc=[
"str (default `'count'` if no arguments are provided, else `'sum'`)",
- "One of `'count'`, `'sum'`, `'avg'`, `'min'`, or `'max'`."
+ "One of `'count'`, `'sum'`, `'avg'`, `'min'`, or `'max'`.",
"Function used to aggregate values for summarization (note: can be normalized with `histnorm`).",
],
histnorm=[