I am trying to combine the 'Table With Expandable Rows' with the 'Table with Selection' because I want to use the mat-checkbox with the expandable row from the angular material site (https://material.angular.dev/components/table/examples). I am unable to get a mat-checkbox to show on a data table. My code is here StackBlitz. When I remove or comment out the mat-checkbox container the table will show but obviously when I re-add it or uncomment it. I need help on how I can get the checkbox to display on an expandable table with rows. Continue reading...