When using `mat-autocomplete` in a `mat-chip-grid`, functionality has changed between versions 15 and 16.
Where you used to be able to type input, press down arrow to a suggestion, and hit enter to get the suggestion included as a chip, you now get the suggestion and the half completed input.
This can be seen in the code I am writing, and even on the
material.angular.io example page
here.
Example steps to recreate:
1. select input box
2. type 'Ap'
3. down arrow to highlight 'Apple'
4. hit enter
5. both 'Ap" and 'Apple' will be chips