apt-get throws to stderr - "Extracting templates from packag

[lioramilbaum]

While using apt-get command, the following message is thrown to stderr
"Extracting templates from packages: 100%"

Is there a reason why? Shouldn't it go to stdout?

The message stands out (red) when using it in a docker build, when it shouldn't. One should persists in keeping the build output errors and warnings free, which means, addressing those red messages.