I think arkenfox is better because you can get updates faster and automatically.
You should be able to get automatic updates on librewolf as well (at least on Linux).
Having to apt-get update && apt-get upgrade regularly is no auto upgrades
Oh I see what you mean, I thought you meant it wouldn't update at all during a normal apt upgrade.
LibreWolf is glorified arkenfox.js. You also have to put your trust into the LibreWolf team so they don't ship you a compromised binary and stuff. I'd prefer Arkenfox for security reasons.
If you're asking, means that you're willing to go through arkenfox configuration, setting up your rules and parameters, etc... So I'd say go for it. You can always go back to LibreWolf.
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