How to use "&amp;" in richtext? I'm currently finishing a client-website which has to be 100% valid HTML5. For one of the sections, I am using a matrix containing rich-text fields. This content is simply shown on the front page.
The name of the client is "E&amp;K".

Requirements:


The output contains HTML tags.
The output has to be 100% valid HTML.


Problem:
The &amp; character won't be escaped to &amp;amp; wherever it is outputted. This breaks the valid requirement. It seems the problem is the input, not the output. However the rich text editor keeps replacing manually placed &amp;amp; with &amp;

How can I get this to work correctly?
You could use Twig's replace filter on output:

{{ entry.richtext_field_handle|replace('&amp;': '&amp;amp;') }}


At first glance I couldn't find a Redactor setting which would help you, but you might want to check yourself, or even write a Redactor plugin.