You're building a custom module and need to lock down sensitive fields—commission rates, margin percentages, internal notes. You add security groups to the XML, restart the server, and... nothing. Was it the group? The record rule? The field-level access? You spend twenty minutes toggling groups in the UI, logging in as test users, and checking the postgres logs. View Access Debugger ends that cycle. Activate debug mode and every field on every form shows a tiny badge: green checkmark if the current user can edit, yellow eye if read-only, red X if hidden by security rules. Click the badge and see exactly which groups control that field, plus the XML location where the restriction was defined. No more guessing. One Odoo consultant saved four hours per client audit after installing this—security reviews that used to require spreadsheets and SQL queries now finish in fifteen minutes. Install it once and never waste another afternoon hunting phantom access bugs.