Backstage is an open framework for building developer portals. Configuration supplied through APPCONFIG* environment variables, for example APPCONFIGbackendlistenport=7007, where unexpectedly ignoring the visibility defined in configuration schema. This occurred even if the configuration schema specified that they should have backend or secret visibility. This was an intended feature of the APPCONFIG* way of supplying configuration, but now clearly goes against the expected behavior of the configuration system. This behavior leads to a risk of potentially exposing sensitive configuration details intended to remain private or restricted to backend processes. The issue has been resolved in version 0.3.75 of the @backstage/plugin-app-backend package. As a temporary measure, avoid supplying secrets using the APPCONFIG configuration pattern. Consider alternative methods for setting secrets, such as the environment substitution available for Backstage configuration.