Do google read our links before javascript changes it?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  Michael Martinez: Let me address two points here, although you`re really only raising one.
  
  FIRST: It is very common for discussion and commenting platforms to create individual URLs for posts or comments. There is no reason NOT to do that. The search engines take these things into consideration and I rarely see individual comments or posts in search results any more. I cannot prove this but my feeling is they are canonicalizing the comments to articles and posts to discussion threads on most standard platforms. There are probably some outliers.
  
  SECOND: You only need to add "nofollow" attributes to links that your users embed in their comments. You should NOT be using "nofollow" attributes when linking to these comment URLs. Every link with a "nofollow" attribute dissipates (into the general Web index) some of the PageRank-like value your site has earned. Google calls this process "evaporation" and they started doing it in early 2008 because people were using "nofollow" attributes on their own links, killing their sites` value in Google`s algorithms. At least through evaporation some of that PageRank is brought back.
  
  Per your specific question, Googlers have said as recently as this year they cannot guarantee that their algorithms would see changes made to link attributes via Javascript. They might or they might not. It depends on too many variables for anyone to be sure. This is not a reliable method of masking markup and it`s not recommended.
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  Nazmun Nahar: Michael Martinez thanks a lot for the detail explanation :) I almost got my solution.
  Just one thing, Google won`t show the comment URL in the search result but Google index those URsL. I`m confused if google considers this pages as thin content (though I believe Google to smart to understand this comment URL).
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  Nazmun Nahar: Michael Martinez FYI, I got an email from Google Search Console about the mobile usability issue of comment URL/pages. So, the URLs are indexed for sure.