Overall, Publii is a blog-oriented CMS, it creates posts and lists them on the index or tag/author pages.
But there is no problem with creating any kinds of pages, just make a custom post template (https://getpublii.com/dev/how-to-create-custom-templates/#how-to-create-custom-templates) and assign it to, for example, the “Contact us” post. And now you can put whatever content you want (e.g. contact form) into the post-your-template-slug.hbs file, while you won’t be able to edit it easily with Publii’s editors, but with a little knowledge of HTML / CSS you can create any site (like most static generators that don’t offer GUI).
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