How to get the string prefixed with “Mat” within curly braces {} and print with the addition of a comma?
e.g.
in:

import { MatSidenavModule } from '@angular/material/sidenav';
import { MatToolbarModule } from '@angular/material/toolbar';
import { RouterOutlet } from '@angular/router';

out:

MatSidenavModule,
MatToolbarModule,

I tried:

awk -F"[{}]" 'BEGIN {/Mat/} {gsub(/ /, "", $2); print $2","}' in

GNU Awk version is 5.0.1.