-`iid` filter has been removed from `GET /projects/:id/issues`[!8967](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8967)
-`GET /projects/:id/merge_requests?iid[]=x&iid[]=y` array filter has been renamed to `iids`[!8793](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8793)
- Endpoints under `GET /projects/merge_request/:id` have been removed (use: `GET /projects/merge_requests/:id`) [!8793](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8793)
- Project snippets do not return deprecated field `expires_at`[!8723](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8723)
- Endpoints under `GET /projects/:id/keys` have been removed (use `GET /projects/:id/deploy_keys`) [!8716](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8716)
## 9.0
- Status 409 returned for `POST /projects/:id/members` when a member already exists [!9093](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9093)
- Moved `DELETE /projects/:id/star` to `POST /projects/:id/unstar`[!9328](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9328)
- Removed the following deprecated Templates endpoints (these are still accessible with `/templates` prefix) [!8853](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8853)
-`/licenses`
-`/licenses/:key`
-`/gitignores`
-`/gitlab_ci_ymls`
-`/dockerfiles`
-`/gitignores/:key`
-`/gitlab_ci_ymls/:key`
-`/dockerfiles/:key`
- Moved `POST /projects/fork/:id` to `POST /projects/:id/fork`[!8940](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8940)
- Moved `DELETE /todos` to `POST /todos/mark_as_done` and `DELETE /todos/:todo_id` to `POST /todos/:todo_id/mark_as_done`[!9410](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9410)
- Project filters are no longer available as `GET /projects/foo`, but as `GET /projects?foo=true` instead [!8962](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8962)
-`GET /projects/visible` & `GET /projects/all` are consolidated into `GET /projects` and can be used with or without authorization
-`GET /projects/owned` moved to `GET /projects?owned=true`
-`GET /projects/starred` moved to `GET /projects?starred=true`
-`GET /projects` returns all projects visible to current user, even if the user is not a member [!9674](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9674)
- To get projects the user is a member of, use `GET /projects?membership=true`
- Return pagination headers for all endpoints that return an array [!8606](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8606)
- Added `POST /environments/:environment_id/stop` to stop an environment [!8808](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8808)
- Removed `DELETE /projects/:id/deploy_keys/:key_id/disable`. Use `DELETE /projects/:id/deploy_keys/:key_id` instead [!9366](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9366)
- Moved `PUT /users/:id/(block|unblock)` to `POST /users/:id/(block|unblock)`[!9371](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9371)
- Make subscription API more RESTful. Use `POST /projects/:id/:subscribable_type/:subscribable_id/subscribe` to subscribe and `POST /projects/:id/:subscribable_type/:subscribable_id/unsubscribe` to unsubscribe from a resource. [!9325](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9325)
- Labels filter on `GET /projects/:id/issues` and `GET /issues` now matches only issues containing all labels (i.e.: Logical AND, not OR) [!8849](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8849)
- Renamed parameter `branch_name` to `branch` on the following endpoints [!8936](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8936)
-`POST /projects/:id/repository/branches`
-`POST /projects/:id/repository/commits`
-`POST/PUT/DELETE :id/repository/files`
- Renamed the `merge_when_build_succeeds` parameter to `merge_when_pipeline_succeeds` on the following endpoints: [!9335](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/)
- Renamed `branch_name` to `branch` on `DELETE /projects/:id/repository/branches/:branch` response [!8936](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8936)
- Remove `public` parameter from create and edit actions of projects [!8736](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8736)
- Remove `subscribed` field from responses returning list of issues or merge
requests. Fetch individual issues or merge requests to obtain the value
- Use `visibility` as string parameter everywhere [!9337](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9337)
- Notes do not return deprecated field `upvote` and `downvote`[!9384](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9384)
- Return HTTP status code `400` for all validation errors when creating or updating a member instead of sometimes `422` error. [!9523](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9523)
- Remove `GET /groups/owned`. Use `GET /groups?owned=true` instead [!9505](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9505)
- Return 202 with JSON body on asynchronous removals on V4 API (`DELETE /projects/:id/repository/merged_branches` and `DELETE /projects/:id`) [!9449](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9449)
-`GET /projects/:id/milestones?iid[]=x&iid[]=y` array filter has been renamed to `iids`[!9096](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9096)
- Return basic information about pipeline in `GET /projects/:id/pipelines`[!8875](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/8875)
- Renamed all `build` references to `job`[!9463](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9463)
- Drop `GET /projects/:id/repository/commits/:sha/jobs`[!9463](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9463)
- Rename Build Triggers to be Pipeline Triggers API [!9713](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9713)
-`POST /projects/:id/trigger/builds` to `POST /projects/:id/trigger/pipeline`
- Require description when creating a new trigger `POST /projects/:id/triggers`
- Simplify project payload exposed on Environment endpoints [!9675](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9675)
- API uses merge request `IID`s (internal ID, as in the web UI) rather than `ID`s. This affects the merge requests, award emoji, to-dos, and time tracking APIs. [!9530](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9530)
- API uses issue `IID`s (internal ID, as in the web UI) rather than `ID`s. This affects the issues, award emoji, to-dos, and time tracking APIs. [!9530](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9530)
- Change initial page from `0` to `1` on `GET /projects/:id/repository/commits` (like on the rest of the API) [!9679](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9679)
- Return correct `Link` header data for `GET /projects/:id/repository/commits`[!9679](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9679)
- Update endpoints for repository files [!9637](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9637)
- Moved `GET /projects/:id/repository/files?file_path=:file_path` to `GET /projects/:id/repository/files/:file_path` (`:file_path` should be URL-encoded)
-`GET /projects/:id/repository/blobs/:sha` now returns JSON attributes for the blob identified by `:sha`, instead of finding the commit identified by `:sha` and returning the raw content of the blob in that commit identified by the required `?filepath=:filepath`
- Moved `GET /projects/:id/repository/commits/:sha/blob?file_path=:file_path` and `GET /projects/:id/repository/blobs/:sha?file_path=:file_path` to `GET /projects/:id/repository/files/:file_path/raw?ref=:sha`
-`GET /projects/:id/repository/tree` parameter `ref_name` has been renamed to `ref` for consistency
-`confirm` parameter for `POST /users` has been deprecated in favor of `skip_confirmation` parameter
-[GitLab v3 API documentation](https://gitlab.com/gitlab-org/gitlab-foss/-/blob/8-16-stable/doc/api/README.md)
-[Migration guide](https://gitlab.com/gitlab-org/gitlab-foss/-/blob/11-0-stable/doc/api/v3_to_v4.md) from
