The "view on Navigator" links on group and software pages don't work properly when built with the --subdirectory flag. The layerURL doesn't utilize the subdirectory prefix, so while the link to the Navigator will open fine it will not retrieve the layer from the site properly.

https://github.com/mitre-attack/attack-website/blob/develop/attack-theme/templates/macros/navigator.html#L20

See also this commit fixing the issue on the gh-pages branch: 13c4653