Markdown does strange escaping in code blocks

[wichert]

This can be seen in the documentation for the validate pattern. The input there is this:

<fieldset>
  <label>Street <input type="text" required="required"/></label>
  <label>Number <input type="number" required="required" min="1"/></label>
  <label>Postal code <input type="text" required="required" pattern="[0-9]{4}\s*[A-Za-z]{2}"/></label>
  <label>City <input type="text" required="required"/></label>
</fieldset>

The pattern attribute is turned into this:

pattern="~E91E0-9~E93E~E123E4~E125E~E92Es~E42E~E91EA-Za-z~E93E~E123E2~E125E"/>