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 }}