Learnt from: smirk-dev
Repo: RocketChat/Rocket.Chat PR: 39625
File: apps/meteor/app/api/server/v1/push.ts:85-97
Timestamp: 2026-03-14T14:58:58.834Z
Learning: In RocketChat/Rocket.Chat, the `push.token` POST/DELETE endpoints in `apps/meteor/app/api/server/v1/push.ts` were already migrated to the chained router API pattern on `develop` prior to PR `#39625`. `cleanTokenResult` (which strips `authToken` and returns `PushTokenResult`) and `isPushTokenPOSTProps`/`isPushTokenDELETEProps` validators already exist on `develop`. PR `#39625` only migrates `push.get` and `push.info` to the chained pattern. Do not flag `cleanTokenResult` or `PushTokenResult` as newly introduced behavior-breaking changes when reviewing this PR.

Learnt from: amitb0ra
Repo: RocketChat/Rocket.Chat PR: 39676
File: .changeset/migrate-users-register-openapi.md:3-3
Timestamp: 2026-03-16T21:50:42.118Z
Learning: In RocketChat/Rocket.Chat OpenAPI migration PRs, removing endpoint types and validators from `rocket.chat/rest-typings` (e.g., `UserRegisterParamsPOST`, `/v1/users.register` entry) is the *required* migration pattern per RocketChat/Rocket.Chat-Open-API#150 Rule 7 ("No More rest-typings or Manual Typings"). The endpoint type is re-exposed via a module augmentation `.d.ts` file in the consuming package (e.g., `packages/web-ui-registration/src/users-register.d.ts`). This is NOT a breaking change — the correct changeset bump for `rocket.chat/rest-typings` in this scenario is `minor`, not `major`. Do not flag this as a breaking change during OpenAPI migration reviews.

Learnt from: amitb0ra
Repo: RocketChat/Rocket.Chat PR: 39647
File: apps/meteor/app/api/server/v1/users.ts:710-757
Timestamp: 2026-03-15T14:31:28.969Z
Learning: In RocketChat/Rocket.Chat, the `UserCreateParamsPOST` type in `apps/meteor/app/api/server/v1/users.ts` (migrated from `packages/rest-typings/src/v1/users/UserCreateParamsPOST.ts`) intentionally has `fields: string` (non-optional) and `settings?: IUserSettings` without a corresponding AJV schema entry. This is a pre-existing divergence carried over verbatim from the original rest-typings source (PR `#39647`). Do not flag this type/schema misalignment during the OpenAPI migration review — it is tracked as a separate follow-up fix.

Learnt from: tassoevan
Repo: RocketChat/Rocket.Chat PR: 39304
File: packages/ui-contexts/src/ActionManagerContext.ts:26-26
Timestamp: 2026-03-04T14:16:49.202Z
Learning: In `packages/ui-contexts/src/ActionManagerContext.ts` (TypeScript, RocketChat/Rocket.Chat), the `disposeView` method in `IActionManager` uses an intentionally explicit union `UiKit.ModalView['id'] | UiKit.BannerView['viewId'] | UiKit.ContextualBarView['id']` to document which view types are accepted, even though all constituents resolve to the same primitive. The inline `// eslint-disable-next-line typescript-eslint/no-duplicate-type-constituents` comment is intentional and should not be flagged or removed.

Learnt from: gabriellsh
Repo: RocketChat/Rocket.Chat PR: 37398
File: packages/fuselage-ui-kit/src/surfaces/FuselageSurfaceRenderer.tsx:357-363
Timestamp: 2025-11-17T15:07:13.273Z
Learning: In packages/fuselage-ui-kit/src/surfaces/FuselageSurfaceRenderer.tsx, IconElement is a presentational, non-actionable element that does not require wrapping in AppIdProvider, similar to plain_text and mrkdwn renderers. Only actionable elements (those with actions, actionId, or interactive behavior) should be wrapped in AppIdProvider.

Learnt from: dougfabris
Repo: RocketChat/Rocket.Chat PR: 39892
File: apps/meteor/client/views/room/contextualBar/Threads/Thread.tsx:150-155
Timestamp: 2026-03-27T14:52:56.865Z
Learning: In Rocket.Chat, there are two different `ModalBackdrop` components with different prop APIs. During review, confirm the import source: (1) `rocket.chat/fuselage` `ModalBackdrop` uses `ModalBackdropProps` based on `BoxProps` (so it supports `onClick` and other Box/DOM props) and does not have an `onDismiss` prop; (2) `rocket.chat/ui-client` `ModalBackdrop` uses a narrower props interface like `{ children?: ReactNode; onDismiss?: () => void }` and handles Escape keypress and outside mouse-up, and it does not forward arbitrary DOM props such as `onClick`. Flag mismatched props (e.g., `onDismiss` passed to the fuselage component or `onClick` passed to the ui-client component) and ensure the usage matches the correct component being imported.

Learnt from: juliajforesti
Repo: RocketChat/Rocket.Chat PR: 40256
File: apps/meteor/client/components/CreateDiscussion/CreateDiscussion.tsx:121-149
Timestamp: 2026-05-06T12:21:44.083Z
Learning: Field wrappers in rocket.chat/fuselage-forms (Field, FieldLabel, FieldRow, FieldError, FieldHint) auto-create htmlFor/id associations, aria-describedby, and role="alert" for errors. Do not manually set htmlFor, id, aria-describedby, or role attributes when using these wrappers. This automatic wiring does not apply to plain rocket.chat/fuselage components, which require explicit ID wiring per the accessibility docs. In code reviews, prefer using fuselage-forms wrappers for form fields and verify there is no unnecessary manual ID/aria wiring in files that use these wrappers. If a component uses plain fuselage components, ensure proper id wiring as per docs.

Learnt from: dougfabris
Repo: RocketChat/Rocket.Chat PR: 40075
File: apps/meteor/client/views/room/modals/FileUploadModal/FileUploadModal.tsx:69-71
Timestamp: 2026-04-10T22:42:05.539Z
Learning: In `apps/meteor/client/views/room/modals/FileUploadModal/FileUploadModal.tsx`, the submit handler converts an empty/whitespace-only description to `undefined` (`description?.trim() || undefined`) intentionally. All downstream image-rendering components (`AttachmentImage`, `ImagePreview`, `ImageItem`, `ImageGallery`) default `undefined` alt to `''`, so the `<img alt="">` attribute is always present. Do not flag this `undefined` conversion as a bug preventing alt text from being cleared.

Learnt from: juliajforesti
Repo: RocketChat/Rocket.Chat PR: 38493
File: apps/meteor/tests/e2e/page-objects/fragments/home-content.ts:60-82
Timestamp: 2026-02-24T19:36:55.089Z
Learning: In RocketChat/Rocket.Chat e2e tests (apps/meteor/tests/e2e/page-objects/fragments/home-content.ts), thread message preview listitems do not have aria-roledescription="message", so lastThreadMessagePreview locator cannot be scoped to messageListItems (which filters for aria-roledescription="message"). It should remain scoped to page.getByRole('listitem') or mainMessageList.getByRole('listitem').