GPL2 + required to have the place to get the recent version

Hello legal,

So I stumbled upon this rather interesting case of a software licensed by

GPL2 but with an extra "clause" to it:
"

# If you enclose this script or parts of it in your software, it has to

# be accompanied by the same license (see link) and the place where to get

# the recent version of this program. Do not violate the license and if

# you do not agree to all of these terms, do not use it in the first place.
"
https://github.com/drwetter/testssl.sh/blob/3b89dc6b0a41299fbf462789998e4c103f4f0210/testssl.sh#L19-L22

The release notes for 3.0. r5 also mentions:
"

This program is licensed under GPL-2. Please note also that if you're using the program for a paid or free public service you need mention where you got this program from.

It seems that the author is trying to prevent people from setting up webpages using this

software as a backend without crediting it. It seems like a reasonable think to ask for.

My question is regarding DFSG compliance around this, I believe there is nothing wrong with

it, but the fact that upstream expose is as GPL-2 seems a little misleading, as it's not plain GPL-2 and I think we should change something in d/copyright to address this.

Are you aware of other software that are in a similar situation? I would like to see what

d/copyright looks like. For this case the package was accepted by ftp-master with a

d/copyright that states it as GPL-2.

Regards,

Samuel Henrique <samueloph>