References to repo files from wiki pages?

The Markdown special references include referencing a file from the repo with (dir/filename.py). The docs warn that “Relative links do not allow referencing project files in a wiki page or wiki page in a project file. The reason for this is that, in GitLab, wiki is always a separate Git repository.” But absolute references like “/dir/filename” also link into the wiki (from the root), not the repo. There’s no way to reference a repo file except with a full http:// sort of link to a file?