Clicking on any place of mat-form-field should display the dropdown

Currently, when I click on input field area the dropdown is appearing. But I want all available “mat-form-field” area should be clickable and on click it can show the dropdown. I tried increasing the “input” field area but it will disturbed the mat-chip-list.
dropdown appear after clicking on input only

Here is the stackblitz link. mat-chip-list with input