Magento 2.2: Element 'remove', attribute 'media': The attribute 'media' is not allowed.

[Tjitse-E]

Preconditions:
Magento 2.2
PHP 7.1
snowdog/frontools 1.5.8
snowdog/theme-blank-sass 0.10.0

Apparently Magento 2.2 is rather strict about the XML configuration. This piece of code:

magento2-theme-performance/Magento_Theme/layout/default_head_blocks.xml

Line 7 in 34316c2

<remove src="css/print.css" media="print" />

Generates the following error in M2.2:

Exception #0 (Magento\Framework\Config\Dom\ValidationException): Element 'remove', attribute 'media': The attribute 'media' is not allowed.
Line: 23

If you remove the 'media' attribute of print.css this issue is resolved.