How to add a new segment for custom dimension?

I have a Custom Dimension called “Project” and I try to create a segment in the GUI, but the Custom Dimension is not visible there and I can’t find anything like “dimension” in the search box.

I was able to load data for this Dimension from the API via the “segment=dimension3==project-a” parameter, but I don’t know what to select in the user interface.

You should be able to type either dimension or project in the dimension search field of the segment creation menu. Then the UI should suggest you several dimension corresponding to your Project custom dimension…

I see also an error in the GitHub repo:

Fixed in the last version of Matomo (4.10.1)