GitLab default autodevops CI: invalid tag name

I am running the latest gitlab 12.4.0-ee in a docker container on Windows. The docker-runner was also configured to be run in a docker executor mode.

For testing purposes I have created a test project, with only a default mater branch in it. Committed some dummy code to repo, and the CI was run automatically. Worth noticing, that the project has no gitlab-ci.yml in it!

Meaning that the default CI that was run is the Auto DevOps CI (I have actually no idea where the template or the source code is located at). This is the default setting in gitlab.

And so, the build has failed with following error:

invalid argument “/master:9456d6a27179d3cf28b7a2670d2a53204fc327aa” for “-t, --tag” flag: invalid

As you see in the error message - the wrong tag is used for docker build command… Is there anything I can do to make the default Auto DevOps just do it’s job without throwing the error? I have not created any scripts so I expect this process to be working out of the box, without any tweaks.

I have found some similar issues on the internet but unfortunately the solution is not applicable to me, as I am using all-default settings provided by gitlab devs.

Here is what supposed to be a fix but I can’t use it:

The tag should be formated like name:version, and you giving it /master:9fa2d4358e6c426b882e2251aa5a49880013614b which is not a valid tag. You could try to delete the / before master

Any thoughts on how to make CI work?