if ( $abbr =~ m/[A-Z]{2,}/ ) {
            my @inlist;
            push(@inlist, $abbr);
            foreach (@inlist) {
               if ( $_ =~ /\./ ) {
                  my @dumm = split(/\./, $_);
                  $inlist[0] =~ s/\.//g;
                  foreach (@dumm) {
                     push(@inlist, $_);
                  };
               };
            };
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From perlsyn:

If any part of LIST is an array, foreach will get very confused if you add or remove elements within the loop body, for example with splice. So don't do that.