1. A computer-implemented method comprising: detecting a resolution of an internet address to a first computing-device address, the internet address being associated with a first domain; storing a domain-name record, the domain-name record associating the internet address with the first computing-device address; using the domain-name record to bind the first domain to the first computing-device address; preventing, until a request to leave the first domain is detected, the first domain from being rebound to a second computing-device address; wherein: using the domain-name record to bind the first domain to the first computing-device address comprises providing the domain-name record in response to a subsequent domain-name-service query for the first domain; preventing the first domain from being rebound comprises: prohibiting, until the request to leave the first domain is detected, modification of the domain-name record; the request to leave the first domain comprises at least one of: a request to navigate to a second domain; a request to terminate a browser window; a request to terminate a browser tab.