Hi, what I did was to create a package with the modified notifications.
You can find the source here:
A very comprehensive tutorial about how to build packages, which is also a prerequisite to use any of my code shared before is available here:
Otherwise you probably have to either add a custom yaml according to Install with Docker — Zammad System Documentation documentation and mount the custom files to the correct directory within the docker container (more info about mounting files docker - How to mount a single file in a volume - Stack Overflow) or enter the container and modify the files manually with docker exec ..., but in the second case the files will be overwritten at every update of the Zammad container.
Maybe someone in the community has a better suggestion, have you already tried the search to see if the Zammad team proposes official solutions?
Best,
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