The format_string() function does half html escaping. It escapes < and >
characters, but does not escape ". Therefore, it put us in a situation
where neither {{}}, nor {{{}}} are suitable in templates. If we use {{}}
for an attribute (like title or aria-label), then < and > characters
will be double escaped. On the other hand, if we use {{{}}} there, a
double quote character will break HTML when it is used in an attribute.
Therefore, neither {{}}, nore {{{}}} are usable in html attributes.
Moreover, The title attribute here was redundant because it had the same
value as the link's text.
Shamim Rezaie