[maddyboo]

Someone should register both spaces.dev and tabs.dev, then set them each up to redirect to the other, but only if the HTTP referer is not from the opposing site, to prevent infinite redirects. Then, the only way to access spaces.dev is to navigate to tabs.dev, and vice-versa.

[syrrim]

Wouldn't work for people with referers disabled. I wonder if browsers have a max redirect count to prevent looping like this?

[majewsky]

Yes they have. In Firefox, look for network.http.redirect-limit in about:config.

[anextomp]

HTTP/-1