406 or "Only HTML requests are supported here"

Cause

The request reached one of the node's web pages instead of its API. This almost always means the API base address in Settings is a poll or overview address, so every path is joined onto the wrong root.

Fix

1. 1Open the platform's Settings.
2. 2Set API address to the API root, for example https://conation.one/api/public.
3. 3Set Sign-up URL to the node's real sign-up address.
4. 4Keep the map paths relative. Do not change them to full addresses.