System Keyboard Lock

2017-04-19: Not yet published to TR even though frontmatter makes it look like it is. Unclear if this is being developed by Web Platform or WICG or neither; claims web Platform. Need Léonie coordination. This spec allows browser to capture keys normally exclusive to OS, need to check if that breaks AT hot keys.
2018-12-12: Appears to never have gone to WG, abandoning.