Feature plan: Step 1 · Step 2 · Step 3 · Step 4

Stage 1 - Register event support

• Changes:

  • Added the site-mutable, default-off FORUM_EVENT_SUPPORT_ENABLED flag in the Authored content group.

  • Exposed its evaluated value to the existing template-rendering data contract.

  • Added evaluator coverage for default and site-enabled behavior.

• Verification:

  • ./v3 test FeatureFlagEvaluatorTest — 14 run, 14 passed.

  • Deployment and external verification: not applicable; this stage changes only the local flag registry and rendering context.

• Notes:

  • The Feature Flags tool enumerates the registry, so the new flag requires no separate settings UI.

Stage 2 - Gate event UI

• Changes:

  • Hid the shared non-compact composer event inputs unless event support is enabled.

  • Suppressed the shared event block on board cards and thread pages unless event support is enabled.

  • Added smoke coverage for default-disabled and enabled compose, board, thread, and Forte surfaces.

• Verification:

  • ./v3 test LocalAppSmokeTest::testEventSupportUiIsHiddenByDefaultAndShownWhenEnabled — 1 run, 1 passed.

  • Deployment and external verification: not applicable; UI behavior is covered by local application renders.

• Notes:

  • The compact QDB composer remains unchanged and event-free.

Stage 3 - Enforce event support on writes

• Changes:

  • Added a pre-write thread-creation guard that rejects non-empty event fields when the site flag is disabled.

  • Added direct write coverage proving disabled event input writes no record, ordinary threads still work, and enabled event input retains all three headers.

• Verification:

  • php -l src/ForumRewrite/Write/LocalWriteService.php and php -l tests/WriteApiSmokeTest.php — no syntax errors.

  • ./v3 test WriteApiSmokeTest::testEventFieldsRequireEventSupportBeforeWriting — 1 run, 1 passed.

  • Deployment and external verification: not applicable; the server-side write contract is covered locally.

• Notes:

  • The compose controller already routes write errors through its standard 400 re-render path, so no new error surface was introduced.

Stage 4 - Verify safe flag transitions

• Changes:

  • Added a site-record toggle regression test for default-disabled → enabled → disabled → re-enabled event rendering.

  • Asserted that both the canonical event record and its read-model values remain unchanged across transitions.

• Verification:

  • php -l tests/LocalAppSmokeTest.php — no syntax errors.

  • ./v3 test LocalAppSmokeTest::testEventSupportTogglePreservesExistingEventData — 1 run, 1 passed.

  • ./v3 test — 882 run, 880 passed, 2 failed: the known unrelated WriteApiSmokeTest::testTaskQueueProcessesQueuedAgentReplyOnce and ::testQdbPermalinkShowsViewersExistingUpvoteAsPressedAndDisabled failures.

  • Reran those two failures directly: 2 run, 0 passed; test history classifies them as long-standing since 2026-10-08 and 2026-10-09 respectively.

  • Deployment and external verification: not applicable; this feature has no deployment or external-service dependency.

• Notes:

  • The test changes only the temporary site's feature-flags record, mirroring an operator toggle without mutating event data.