Motivation

The Browser SDK shares session state across tabs via cookies/localStorage, but has no way to identify which specific tab produced a given event. Adding tab.id enables distinguishing events from different tabs within the same session, enabling tab-level correlation between RUM and Logs.

Reference: browser-sdk#4184

Changes

• Add optional tab object with required id (UUID) to _common-schema.json, at the top level alongside usr, account, connectivity, etc.
• Regenerate TypeScript definitions
• Add samples/rum-events/view-with-tab.json as a sample event exercising the new field

Schema

"tab": {
  "type": "object",
  "description": "Tab properties",
  "required": ["id"],
  "additionalProperties": true,
  "properties": {
    "id": {
      "type": "string",
      "description": "UUID of the browser tab",
      "pattern": "^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}$",
      "readOnly": true
    }
  },
  "readOnly": true
}

Notes

• tab is optional at the top level — only browser emits it; existing non-browser events remain valid
• id is required when tab is present (consistent with account)
• additionalProperties: true for future enrichment (consistent with usr and account)