When we define a
<meta name="viewport"> there are two parameters that we can use that affect accessibility:
user-scalable="no": disables browser zoom on a web page
maximum-scale: limits the amount the user can zoom
Both are problematic for users with low vision who rely on browser zoom to see the contents of a web page. It is better not to define them and to leave complete freedom to the user to manage the zoom as needed when visiting our website.
Therefore the ideal definition is:
<meta name="viewport" content="width=device-width, initial-scale= 1" />
This is a perfect example of how not to use
<meta name="viewport" />.