I was going through the markup of one of blogs with W3C validator and I came across this remark there is no attribute "data-rel".
When I checked it out, I found the problem came from Google + widget which I pasted it on my sidebar.
Among the Google Plus code in this widget, there is this: data-rel="author" which causes this there is no attribute "rel" problem.
After fiddling around, I managed to get the "data-rel" glitch fixed.
Here is a short and easy-to-understand tutorial how to remove no attribute "data-rel" problem.
How T Get Rid Of No Attribute "data-rel"
1. Go to WordPress Dashboard.
2. Click "Appearance".
3. Click on "Widget".
4. Look for the Google Plus widget wherever you paste it .
5. Open up the code and look for: data-rel="author".
6. Change the word data-rel to target.
7. Now it should look like this: target="author"
8. Click the "Save" button.
That's all.Now the no attribute "data-rel" invalid markup should be gone now.
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