@gskharmujai - i reviewed the patch today and feature seems to be working.
Ho...

@gskharmujai - i reviewed the patch today and feature seems to be working.

However, I have second thoughts about getting into the text-formats configurations. And on trying few things today I think we could simply create a configuration form at say 'admin/config/content/linkit/autocomplete-minlength' which allows to save integer value for min-length. (default value 1)

We could pass this min-length from processLinkitAutocomplete function of Drupal\linkit\Element\Linkit class to /js/autocomplete.js using drupalSettings. Off-course we will have to define drupalSettings library as a dependency in libraries.yml.

I think this solution will be easier to maintain in the long run.