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MacOS:
$ brew install libsodium
Ubuntu (16.04 LTS):
$ apt install libsodium18
Ubuntu (18.04 LTS):
$ apt install libsodium23
Ubuntu (14.04 LTS):
You can find the appropriate package files here:
https://launchpad.net/~phoerious/+archive/ubuntu/keepassxc/+sourcepub/8814980/+listing-archive-extra
The `sudo` command might be needed on Linux, and if the screen prompts you to enter a password, type your password and press enter.
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