#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template <typename T> using o_set = tree<T, null_type, std::less<T>, rb_tree_tag, tree_order_statistics_node_update>;
// #define int long long
#define endl '\n'
#define F first
#define S second
#define pii pair<int, int>
#define sz(x) (int) x.size()
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

void solve() {
    int n, m; cin>>n>>m;
    vector<vector<char>> v(n, vector<char>(m));
    for(auto &x : v) for(auto &y : x) cin>>y;

    auto get = [&] (int i, int j) {
        int mn = 1e9;
        int ni = i, nj = j;
        while(nj < m && v[i][nj] == '+') nj += 1;
        mn = min(mn, nj - j);
        nj = j;
        while(nj >= 0 && v[i][nj] == '+') nj -= 1;
        mn = min(mn, j - nj);

        while(ni < n && v[ni][j] == '+') ni += 1;
        mn = min(mn, ni - i);
        ni = i;
        while(ni >= 0 && v[ni][j] == '+') ni -= 1;
        mn = min(mn, i - ni);

        return 1 + 4 * (mn - 1);
    };
    
    int ans = 0;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) if(v[i][j] == '+') {
            ans = max(ans, get(i, j));
        }
    }

    cout<<ans<<endl;
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int t = 1, c = 1; cin>>t;
    while(t--) {
        // cerr<<"Case "<<c++<<": \n";
        solve();
    }
}