Support typeahead suggestions with spaces in search terms (e.g. @firstname lastname)

I’m interested in using the typeahead plugin for cases where suggestions may contain spaces, such as mentioning users by full name (e.g., @firstname lastname). Currently, the typeahead seems to match only single “words” without spaces after the trigger.

Would it be possible to add support for typeahead suggestions where the search term contains spaces? For example, typing @first l would offer @First Last as a match and allow inserting the full name including the space.

This would be really useful for cases like user mentions, tags with spaces, or other multi-word entries.

This could possibly be supported by allowing the users to configure the allowed (or ignored) escape characters or a trigger regex string.

Start by locating the typeahead plugin's trigger matching and suggestion insertion entry points. Reproduce the reported @first l case and trace where spaces stop being included in the search term. Done means multi-word suggestions such as @First Last can be matched and inserted while existing single-word behavior remains supported.