The final stable Apache version supported on Debian is 2.4.10, whilst to configure HTTP2 requires a minimum Apache version to be 2.4.12.
There are workarounds available, which require test Debian releases to be installed and then enabling HTTP2, however I am not sure about installing a test release on a production web-server.
Surprisingly, in the last 2 days I have been looking, I have not been able to find another solution for enabling HTTP2 on Apache 2.4.10 on Debian. (Which necessarily means that running Apache on Debian is useless as far as HTTP2 is concerned?)
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