#include<stdio.h>
#include<iostream>
#include<string.h>
#include<math.h>
#include<algorithm>
using namespace std;
const int N = 1005;

int n,m;
char a[N][N];
int mp[N][N];
int L[N],R[N];
void input(){
     memset(mp,0,sizeof(mp));
     for(int i=1;i<=n;i++){
            gets(a[i]);
            for(int j=1;j<=m;j++){
                if(i==1) {     ///预处理mp
                    if(a[i][(j-1)*2]==‘R‘) mp[i][j]=0;
                    if(a[i][(j-1)*2] ==‘F‘) mp[i][j]=1;
                }else{
                    if(a[i-1][(j-1)*2]==‘R‘) {
                        if(a[i][(j-1)*2] ==‘R‘) mp[i][j]=0;
                        if(a[i][(j-1)*2] ==‘F‘) mp[i][j]=1;
                    }
                    else {
                        if(a[i][(j-1)*2] ==‘R‘) mp[i][j]=0;
                        if(a[i][(j-1)*2] ==‘F‘) mp[i][j]+=mp[i-1][j]+1;
                    }
                }
            }
        }
    /*for(int i=1;i<=n;i++){ //test
        for(int j=1;j<=m;j++){
            printf("%d ",mp[i][j]);
        }
        printf("\n");
    }*/
}
int main()
{
     int tcase;
     scanf("%d",&tcase);
     while(tcase--){
        scanf("%d%d",&n,&m);
        getchar();
        input();
        int mx = -1;
        for(int k=1;k<=n;k++){
            L[1]=1;
            R[m]=m;
            for(int i=2;i<=m;i++){ ///向右延伸
                int t = i;
                if(t>1&&mp[k][i]<=mp[k][t-1]) t = L[t-1];
                L[i] =t;
            }
            for(int i=m-1;i>=1;i--){
                int t = i;
                if(t<m&&mp[k][i]<=mp[k][t+1]) t = R[t+1];
                R[i] = t;
            }
            for(int i=1;i<=m;i++){
                if((R[i]-L[i]+1)*mp[k][i]>mx)  mx = (R[i]-L[i]+1)*mp[k][i];
            }
        }
        printf("%d\n",mx*3);
     }

}