If a user has a keyword with a punctuation mark in it like an exclamation point, WordPress strips it out when it is added to the slug. Therefore, we should detect if Keyword has a punctuation mark in it and output a different notification for the slug alerting users to this.

1.Add a keyword with an ending mark like: FRITZ!App WLAN

2. See it appear as a slug with out the exclamation point

3.See notification outputted Keyphrase in slug: (Part of) your keyphrase does not appear in the slug. Change that!

4. We should therefore, improve that notification by alerting users that they have a mark in the slug.

Not sure if Yoast was set-up to do that previously based on these two issues? #1778 and #1608

Technical info

• Platform: WordPress
• Platform version: 5.1.1
• Yoast SEO version: 11

Which browser is affected (or browsers):

• [x ] Chrome
• Firefox
• Safari
• Other

If relevant, which editor is affected (or editors):

• [ x] Classic Editor
• Gutenberg
• Classic Editor plugin