LinkRenderer always adding rel="noopener noreferrer" when opening in new window

[joelclermont]

Version(s) affected

2.4.0

Description

When an external link is set to open in a new window, the noopener and noreferrer values are being added, even though my config has disabled them.

How to reproduce

Here is my setup

        $config = [
            'external_link' => [
                'internal_hosts' => ['my-internal-domain.com'],
                'open_in_new_window' => true,
                'nofollow' => '',
                'noopener' => '',
                'noreferrer' => '',
            ],
        ];

        $converter = new GithubFlavoredMarkdownConverter($config);
        $converter->getEnvironment()->addExtension(new ExternalLinkExtension());

        $converter->getEnvironment()->addRenderer(FencedCode::class, new FencedCodeRenderer());
        $converter->getEnvironment()->addRenderer(IndentedCode::class, new IndentedCodeRenderer());

Markdown input:

This is an external link [Google](https://google.com/).

HTML output:

<a target="_blank" href="https://google.com/" rel="noopener noreferrer">Google</a>

Expected output:

<a target="_blank" href="https://goggle.com/">Google</a>

[joelclermont]

And if I change the config for open_in_new_window to false, the rel attribute is not rendered (as expected).

[colinodell]

It looks like this is happening because LinkRenderer adds a default rel attribute if none is set:

commonmark/src/Extension/CommonMark/Renderer/Inline/LinkRenderer.php

Lines 56 to 58 in 564525f

	if (isset($attrs['target']) && $attrs['target'] === '_blank' && ! isset($attrs['rel'])) {
	$attrs['rel'] = 'noopener noreferrer';
	}

Making ExternalLinkProcessor set the rel attribute to false should prevent this. I'll get a PR together for this shortly :)

[colinodell]

Fixed in v2.4.1 :)

[joelclermont]

Beautiful!! Thank you!