Minimum system requirements

[ghost]

I tried to compile ricochet-refresh on Ubuntu 16.04 x86 by updating many libraries, but failed. However, I have identified flaws in the minimum system requirements you mentioned.
https://github.com/blueprint-freespeech/ricochet-refresh/blob/main/BUILDING.md

1. You didn't specify that it is required to clone submodules: cd ricochet-refresh && git submodule update --init --recursive
2. Since c++2020 standard is used (--std=c++2a), at least gcc8 is required, maybe newer (gcc10)
3. openssl 1.0.2 is not suitable, needs openssl 1.1.0 at least, maybe openssl 1.1.1
4. There is an error in your description. The minimum Qt is not 5.1.0, but 5.10

[m-simonelli]

1. This will be fixed in the docs when docs: clone with --recurse-submodules #109 is merged
2. If building with the logger enabled, GCC 11 is required (I think experimental/source_location is available in earlier revisions, but I can't find the exact version), or clang 9. If the logger is disabled, I think GCC 8 or clang 6 is required.
3. Yes, this is required by Qt > 5.15
4. The minimum version of Qt required is 5.15, as we utilize the onFoo syntax introduced in 5.15 for our QML

This will all be added in the docs as we migrate to a new CMake build system.
RE compiling on Ubuntu, if you're on the latest LTS release, you'll have to install Qt from their website (or a PPA), as the latest version available in the repositories is 5.12.