Error message invalid argument supplied for foreach()

I had following error message after a click on a Artikel Headline
Warning: Invalid argument supplied for foreach() in .../templates/gk_creativity/html/com_content/article/default.php on line 14

I found this Workaround:
https://www.gavick.com/forums/fest-joom ... 24605.html
---> put the "@" sign right before "foreach".

The REsult of putting the @ was:

Parse error: syntax error, unexpected 'foreach' (T_FOREACH) in .../templates/gk_creativity/html/com_content/article/default.php on line 14

What can I do now?

I just found out, that I get this error only if I added the article from the frontend. If I add articles form backend into the same categorie I get nothing. Could this be a hint to sove the issue?

The Message won't come back if I save the article once from the backend.

for now I changed it to, but it's not the real fix for the Problem.
Do you've a glue what's the Problem is and how to fix it?
txs for your help

if (!empty($attribs)) {
foreach($attribs as $key => $value) {
if($value != null) {
$params->set($key, $value);
}
}
}