The API Reference TOC is incomplete

[yordan-mitev]

Describe the bug

1. For complex components with a rich API, the API Reference TOC is incomplete.
2. The TOC remains under the footer when you scroll to the bottom of the page.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://docs.telerik.com/aspnet-core/api/Kendo.Mvc.UI.Fluent/GridBuilder#allowcopysystemaction.
2. Click the last item in the "IN THIS ARTICLE" TOC on the right-hand side of the page.
3. Scroll down further and you will notice that there are a number of headings that aren't visible in the TOC. When you reach the end of the page, the footer will cover the TOC.

Expected behavior

1. A scroll bar must allow you to scroll the TOC.
2. The footer must not cover the TOC.

Screenshots