Toggle each abbreviation-set (i.e. all instances of an abbr. at once) between its short and long form
An overview of how often it's used
An option to create a table of abbreviations
And of course to let the software handle the task of finding the first instance of the abbreviation and explaining it there, while keeping the short form in all subsequent instances.
Auto-search the document for unlinked instances of the abbreviation so the user can easily see a list of all of those and manually add/exclude those from being linked.
Useful options:
Light reading: https://elifesciences.org/articles/60080