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Trailing slash on void elements has no effect and interacts badly with unquoted attribute values.
<meta name="viewport" content="width=device-width, initial-scale=1.0" />

How to remove slash?
<meta name="viewport" content="width=device-width, initial-scale=1.0"> This is good

Comments

e-k-b’s picture

<img{{ attributes.addClass(classes) }} />
<img{{ attributes.addClass(classes) }}> This is good
you can edit in the template image.html.twig

How to remove slashes from a number of lines in the head?
<meta charset="utf-8" />
<meta charset="utf-8"> This is good

e-k-b’s picture

Drupal 11.2.9 It contains 201 spaces and slashes. 
Why are they there?