common: drop compatibility copyright rel

Alternate value as supported by old Presto browsers, apparently deprecated
in current standards according to <https://validator.w3.org/>:

> The keyword copyright for the rel attribute should not be used.
> Consider using license instead.

Nobody cares about (or uses) Opera anymore :/

diff --git a/common.inc.plp b/common.inc.plp
index 5f7cb25f394046b8963f5b9b85d6292ba0f0f55a..e5292ba46abd1365258e2ca7e812396deed7cc98 100644 (file)
--- a/common.inc.plp
+++ b/common.inc.plp
@@ -168,7 +168,7 @@ sub Html {
        created by <a href="http://shiar.nl/" rel="author">Shiar</a> •
        <a href="http://www.fsf.org/licensing/licenses/agpl-3.0.html"
         title="Licensed under the GNU Affero General Public License, version 3"
-        rel="license copyright">AGPLv3</a>
+        rel="license">AGPLv3</a>
 EOT
                say sprintf '• %.3fs', Time::HiRes::tv_interval($Time) if $Dev and $Time;
                say '</p>';