For security reasons, the browser command must not contain whitespace or start with a slash. The purpose of this mechanism is to avoid commands like rm -rf / or /tmp/rootkit.
Public beta test started in February 2005. The first public release was in March 2005. The project was rewritten completely between v0.2.6 and v0.3-alpha1, and again for v0.4-beta1 (transition to the Django framework).