This paper introduces webPASS, a lightweight, web-native PASS modeling environment designed to democratize access and foster collaboration. webPASS integrates a metamodel-based validation engine to ensure semantic consistency, supports real-time multi-user editing with change tracking, and allows customization and integration with existing S-BPM toolchains. The frontend is based on TypeScript, Vue 3, and Pinia, providing an interactive user interface. The backend facilitates seamless data exchange between clients, enabling communication through WebSocket connections. The proposed model editor utilizes JSON-LD as the internal representation format for models, as it offers a standardized, flexible, and extensible approach to representing complex data structures. Our solution eliminates traditional barriers to entry, thus making advanced process modeling accessible to a wider audience. The integrated versioning capabilities allow users to track changes, revert to previous states, and branch models for experimental modifications. This functionality is critical for maintaining audit trails in regulated industries and academic research.