Warnings for sharing links in Google Search Console

I'm suddenly getting warnings that links to pages on my site are "indexed but blocked by robots.txt." All of the links Google is reporting have something like this appended to the URL share=pocket?nb=1, sometimes it will be Facebook or Twitter instead of pocket.

Is that a problem? The main links those are appended to are being indexed just fine, it's just that it's somehow picking up on the shareable versions, which one wouldn't want indexed I would think.

If you google search share=pocket?nb=1 there's nearly seven million results, not one of them properly indexed with a description.