The preview link in the post editor uses target="wp-preview-1234" where 1234 is the post ID. That means there’s only ever one tab with the preview of a specific post. If you preview multiple times, it always updates refreshes the existing named tab rather than spawning a second, third, or fourth tab.

(Tangent: I’ve seen people accidentally spawn multiple Edit screens of the same post by opening a preview and then clicking the “Edit Page” button in the admin bar. I wonder if it’s possible for a page to name its own tab when opened—not as a new tab—so that the edit links could also prevent people from editing the same page in multiple tabs. I’m guessing no, but maybe there’s some trickery out there that makes it possible.)

I didn’t knew this, as I am newbie to web development. Thank you for sharing this information. Love to know more .

Thanks for the answer! I understood the difference between “blank” and “_blank”. If i have opened two webpages website.com which uses target = “newTabEveryTime”, for all the hrefs on website.com, it opens two new tabs for the two instances of website.com. Does that have anything to do with tabId? I would really like to find a way a href from any page of the website.com (if you work with lets say 15 opened tabs of the website.com content) to open always in only one new tab.

I still think it’s an attribute of the past, javascript was simple to implement.

Maybe a framework required it, does anyone know?

The example above is for target=blank (without underscore), not target=_blank (with underscore). Also,

In the case of the no-underscore target=”blank”, the blank part is just a name. It could be anything. It could be target=”foo” or, perhaps to foreshadow the purpose here: target=”open-new-links-in-this-space”.
And,
The difference:
target=”_blank” is a special keyword that will open links in a new tab every time.
target=”blank” will open the first-clicked link in a new tab, but any future links that share target=”blank” will open in that same newly-opened tab.

Do not forget security concerns when you use target attribute like explaineed in
https://medium.com/sedeo/how-to-fix-target-blank-a-security-and-performance-issue-in-web-pages-2118eba1ce2f

I think the thing is every day born mullions of babies and every day thousands people learning something new. That’s why posts with simple and easy info are actual.

If I didn’t blog things because I was worried that some people might already know it, there would be zero blog posts on this site.

Alex Yumashev, over at Jitbit, has an excellent explanation of the issue(s):
Target=”_blank” – the most underestimated vulnerability ever

Remember targets are a holdover from before we had Ajax and people would use Frames to to update portions of the page with content from the server. Targets were meant to have semantic names like “shopping-cart” or locations like “right-sidebar”. Latterly naming a frame or window “blank” doesn’t make much sense.