There are some unnecessary files hanging in isos from a long time, from about 12.04 in /usr/share/python-apt/templates. They are not big, but not relevant. Blankon, Tanglu, gNewsense, even Debian.
Did anyone comment on the bug report?
Well, they’re still there (18.04 LTS)! So, do they have a purpose.
This topic has become a Mystery!
The only templates Ubuntu needs are the Ubuntu ones, not the junk that is there. It looks like some dev sometime ago had pulled few packages from those distros, but forgot the templates. Just delete them.
You can also see such stuff everywhere, for example, in /etc/grub.d/05_debian_theme. There also it mentions Tanglu 3 times, meaning the file might have been copied from Tanglu. They are simply harmless stuff, though.
Did you report it? Got the bug number?
Those templates are there because the
python-apt package is shared between these different distros.
It’s probably possible to make the packaging more complicated so that it only installs the templates actually used on the distro.
I have deleted them in every Ubuntu (& derivatives) I had been installing last few years. Nothing happens to the upgrade process without the templates of Blankon, Tanglu etc.
Blankon, Tanglu, Debian or gNewsense wouldn’t share Ubuntu templates in their distros, would they?