error message on Google Chrome console:
Specification mandate value for attribute async
That would happen if we generated
XML page which acted as
XHTML. And we forgot to define the value for a particular
HTML element attribute.
In this case, the value for
async attribute (in
It looked like this
Earlier, it was like this:
XHTML page wouldn't be rendered. It was just blank, but still with the
XML attached (if we view the page source/inspect element).
To fix that, put the value for that attribute. Like so:
On other browser
On Firefox or IE10+ or Safari or other, it has different
error message. But that's the general method to fix it.