Created attachment 10328 [details] proof I download a deb file. I open a terminal to install it. nacia@alt ~/Downloads> sudo apt-get install ./qapt-deb-installer_3.0.5-1ubuntu1_amd64.deb [sudo] password for nacia: Reading Package Lists... Done Building Dependency Tree... Done E: Couldn't find package ./qapt-deb-installer_3.0.5-1ubuntu1_amd64.deb nacia@alt ~/Downloads [100]> ls |grep qapt qapt-deb-installer_3.0.5-1ubuntu1_amd64.deb Screenshot as proof.
why .deb? ALT Linux is RPM based
Alt uses apt-rpm (https://en.wikipedia.org/wiki/APT-RPM) and does not support deb.