Draft changelog: XAA broadcast start and end events

[mintlify]

Summary

Adds an Aug 21, 2026 changelog entry for the new broadcast.start and broadcast.end events on the X Activity API.

Changes

• New Update block at the top of changelog.mdx describing the two new public broadcast events, filter (user_id), and auth options (app-only or user-context), with a link to /x-api/activity/introduction.

Context

Only one product-facing change shipped since the Aug 13, 2026 entry:

• PR Add broadcast.start and broadcast.end events to X Activity API #324 — Add broadcast.start and broadcast.end events to X Activity API.

Other PRs merged in the window were docs-only and excluded from the changelog:

• PR Add delete-chat-messages to Chat API side nav #323 — added delete-chat-messages to the Chat API side nav (endpoint page already existed).
• PR Draft from Aug 20 #322 — added Vista Social to the enterprise customer directory.
• PR Fix Trends by WOEID response docs: remove tweet_count #315 — corrected GET /2/trends/by/woeid/{woeid} docs (removed tweet_count which was never returned by the API).

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Project	Status	Preview	Updated (UTC)
x-corp	🟢 Ready	View Preview	Aug 21, 2026, 8:08 PM

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