Not the main point of the article, but he makes a comment that doesn't sit well with me.<p>> Also for SEO consideration, rel="nofollow" is also recommended.<p>If you are linking to another site, that helps said site's SEO ranking. If you use this in a way that the search engine views as cheating, the other site is penalized.<p>But as long as you and the other site are being fair, then you SHOULD link to them - they are obviously providing good content that you think is important, so why try to hog the credit and not give them the ranking they deserve.<p>Sitye like Stackoverflow do this to cut down on spam, (and perhaps because they want Google to view them as the original), but for a blog or whatever, why would you recommend this?
Previous discussion: <a href="https://news.ycombinator.com/item?id=12380671" rel="nofollow">https://news.ycombinator.com/item?id=12380671</a><p>There were some high profile sites affected by this by the way, I think it was Instagram where it actually went wrong.
There are performance implications to adding noopener, as outlined in in<a href="https://jakearchibald.com/2016/performance-benefits-of-rel-noopener/" rel="nofollow">https://jakearchibald.com/2016/performance-benefits-of-rel-n...</a><p>While the above link suggests noopener is beneficial to add as it will prevent the parent JS process from being paused by long running scripts in the child process, it <i>may</i> actually slow down the site being <i>opened</i> because of the additional time required to initialize the new child's process.<p>It also prevents sites that want to auto-close their opened tab/popup, like Facebook and other sharing sites, from being able to call `window.close` after sharing is complete.