Dividers

[NFanoe]

Is it possible to add a divider or a piece of text with no link in the menu? To divide the menu items?

[lukasgeiter]

Not really. Since MkDocs doesn't support such a feature, that's not something this plugin can add.
If you're using the material theme though, you might be interested in this feature: https://squidfunk.github.io/mkdocs-material/setup/setting-up-navigation/#navigation-sections