I design, develop, deploy, teach, train, coach and speak software. My topics are Security & Trust, the Web, Data Access
& Performance, Scalable & Testable Design, Distributed Systems & Services.
As Visual Studio keeps forgetting the settings that also affect validation and falls back to the oh-so-90-style-2.1-css-version just delete ALL other schemas.
Thanks to the industry known Sweat Swank for searching the registry key.