gitlab webhook payload ref conflicts with pipeline trigger api

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webhooks are supposed to be used to trigger pipelines: docs.gitlab.com/ee/ci/triggers/#using-webhook-payload-in-the-triggered-pipeline

trigger api accepts ref parameter to run a pipeline for certain branch:

curl --request POST \
     --form token=TOKEN \
     --form ref=main \
     .../api/v4/projects/9/trigger/pipeline"

Webhook payload has a ref property, that states from what ref it was triggered:

{
  "object_kind": "push",
  "event_name": "push",
  "before": "972f566cba6d725b6079c8cc2166bd523dd3c8e2",
  "after": "5df16ebcac9c54999ce606523694f77cf705db65",
  "ref": "refs/heads/v3",
  "checkout_sha": "5df16ebcac9c54999ce606523694f77cf705db65",
  "message": null,
  "user_id": 1,
  ....
}

As a result, when a webhook is triggering a pipeline in another project, it's ref property is treated by trigger api as a ref parameter for target branch, resulting in webhooks sent not from main ref fail with {"message":{"base":["Reference not found"]}} error.

What will happen if add ref to trigger url (.../api/v4/projects/9/ref/master/trigger/pipeline)?

Payload will be broken:

This makes literally impossible to use webhooks with external build pipeline for branches other then master