Improve adding items to large alphabetically-sorted documents

Adding new rems to a large alphabetically-sorted documents is not great at the moment.

The way I normally do it is I copy a concept name at the beginning of the document. The concept then gets sorted but the app does not navigate to it automatically. So I have search for this newly added concept with ctrl+F.

Additionally, the performance in large documents is pretty bad, making the whole workflow cumbersome.