Can't install QCLean on Safari anymore

[JuergenSimon]

Downloading the extension and installing it by double-clicking for example does no longer work. Safari refuses by showing an error message:

However, trying to install from Gallery does nothing. QCLean does not appear in the list of extensions at the Safari Extensions Gallery either.

How are Safari users supposed to install the extension?

[qcl]

Thanks for reaching out, I stopped update the version for Safari after they started charging for singing certification of Safari extensions, I would check is there any way I can upgrade this extension for Safari users.

[qcl]

Just checked Apple's document, the old style extension safariextz is deprecated. I would try to think a way to renew it.