Answering https://nlnetlabs.nl/pipermail/unbound-users/2019-June/011579.html:
User, I think that if you only know to install new packages by apt-get, you will have to wait until a new version will be available at some trusted apt-get able repository. When that happens, adding a repository to apt, or downloading a deb directly, will be meaningful. It could be that a newer version than the one you got is already available at unstable. Do not that you might also have to install the right dependencies. Things might turn out messy. You might query Debian documentation, or mailing list, how to convert a source package to a deb binary package.
