Bug: Webhook push event payload missing non-main-branch-commits

As part of the ionic framework CI/CD workflow I setup my Gitlab account with said framework using the webhook on-push event.
The webhook pushes the latest commits on-push to the framework where I am then able to select a commit for the build pipeline.
I am using this setup now for ~4 weeks and until yesterday everything was working flawless. But then my commits were not showing up anymore in the framework.

At first I thought the issue might be with Ionic but using the “Test” button on the webhook page showed, that the payload sent via the webhook was missing the data.


I have a main branch main and 3 sub-branches dev, beta, prod

In “Webhooks > Recent deliveries” the payload send via the webhook can be reviewed.
The status says “OK 200”, but “Show details” shows it contains only the latest commits of my main branch but not the commits to my sub-branches.

(1) Using unique commit names
As my sub-branches are mostly containing equally named merge branches ('merged main into prod') I thought maybe it is because they have the same name and are “only” merge commits that causes them to be ignored.
So I deliberately pushed some unique commits to each of my sub-branches.
But with no changes to the webhook payload.

(2) Pushing branches one by one
Then I thought maybe they are ignored because I pushed my branches including main at the same time.
So after some additional filler-commits I pushed all branches individually.
But again - none of the commits to the sub-branches show up in the webhooks payload.

(3) Setting a value for the ‘branch name’ field
The field for “branch branch” is empty (to include pushes to all branches, not only a particular one).

I then put the name of one of my sub-branches into the “branch” field and tested again.
But the payload sent included again only the latest commits to the main branch

Note: the findings of (3) might actually show yet another issue (committing the data for the wrong branch) - or maybe the two problems are linked

Oh and I am talking about the general Gitlab service and web interface … nothing selfhosted … am I even in the right place. The help pages says that this should be 13.12.0-pre 85b73092d87