What are weak link links on Facebook?

Question

I did not find anything about the purpose of this small icon next to the name tag (referenced by the red arrow in the image above) from the Facebook API documents. Honestly, this is the first time I have seen this. It still works like a regular name tag, only the difference is the mysterious icon and the gray name.

<a class="profileLink weakReference" href="facebook_profile_link" ... 

Answer 1

I got an answer! No, this is not due to a verified account. Checking profiles shows a blue mark. Considering that such a symbol appears in the following case when you mark a friend in a closed group, this friend will not be notified of the tag or notifications. This symbol then appears in front of his / her name.