The wiki instructions mention installing package
manjaro-printer then go on to give instructions which require a further undocumented package installation
system-config-printer. This should be added.
Meta-issue: I would have made the change myself, but the account creation page repeatedly rejects 100% correct submissions (AFAICT) with an error regarding a (non-existent) captcha. The real-human-test field, which I’m guessing is what the error really refers to, should contain the URL of this site (I’m forbidden to include the URL here, I now find), should it not? If so, there seems to be a defect somewhere in the stack that is causing these rejections. At the very least, the error message is misleading.