User story & summary:

As a editor with extended rights with edit permissions for the Community Configuration form, I want the Save changes button to be visible from wherever I am in the form, because then it's clear that I need to Save changes before my updates goes into effect.

As a logged out visitor or editor without permissions to edit the Community Configuration form, I want the Save changes button to be visible from wherever I am in the form, because it will be disabled and that helps make it clear that I can't edit the form.
Follow up work in: T363525: Community Configuration edit form: protected / read only view

Details:

This task is important because it will improve UX and ensure the Community Configuration form adheres to the Codex form guidelines:
https://doc.wikimedia.org/codex/latest/style-guide/constructing-forms.html#footer

The footer of a form should be fixed to the bottom of the viewport, with a background and top border to separate itself from the form itself. This ensures that any related actions are in the same location at all times and are always accessible while scrolling. For forms that exist within a Dialog or smaller container, the actions should come directly after the last field.

Design:

[[ |Figma designs]]

Acceptance Criteria:

Given I'm viewing the Community Configuration form,
Then the "Save changes" button is part of a fixed footer and always visible.