A host computer system may be configured to connect to a network. The host computer system may be configured to implement a workspace and an isolated computing environment. The host computer system may be configured to isolate the isolated computing environment from the workspace using an internal isolation firewall. The host computer system may be configured to receive a request to communicate with a first network destination. On a condition that the first network destination is determined to be trusted, the processor may be configured to communicate with the first network destination via a first browser process executed in the workspace. On a condition that the first network destination is determined to be untrusted, the processor may be configured to communicate with the first network destination via a second browser process executed in the isolated computing environment.