local Demo not working

[wernerjoss]

first, sorry for bothering here, but I'm a hugo beginner and tried to get this working.
having completed all steps from the tutorial (and changed baseurl = "http://localhost" in config.toml) I get this:

ERROR 2024/02/19 10:46:17 render of "page" failed: "/home/josswern/docker/hugo/src/hps_example/layouts/galleries/single.html:7:15": execute of template failed: template: galleries/single.html:7:15: executing "galleries/single.html" at <.URL>: can't evaluate field URL in type *hugolib.pageState Error: Error building site: failed to render pages: render of "page" failed: "/home/josswern/docker/hugo/src/hps_example/layouts/galleries/single.html:7:15": execute of template failed: template: galleries/single.html:7:15: executing "galleries/single.html" at <.URL>: can't evaluate field URL in type *hugolib.pageState

when trying to run the demo with hugo -w server
any hints how to solve this ?