We’re aware of this issue. The problem is that the auto pop-up window on Macs for logging into a captive portal (such as the WiFi Configurator) does not support web sockets, which the configuration page currently uses. We’re going to re-work that page to use plain HTML so that the auto pop-ups work on all platforms.
In the meantime, please open up your full Safari or Chrome web browser and type farmbot.io/setup. You will be redirected to the configuration page, and the full web browser should support websockets.