#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ALLAHU_AKBAR ios::sync_with_stdio(false); cin.tie(nullptr);
void sir() {
ll n, m;
cin >> n >> m;
vector<vector<char>> grid(n + 1, vector<char>(m + 1));
bool got = false;
ll cp = 0;
for (ll i = 1; i <= n; i++) {
for (ll j = 1; j <= m; j++) {
cin >> grid[i][j];
if (grid[i][j] == '+' && (!got)) {
got = true;
}
}
}
if (!got) {
cout << 0 << endl;
return;
}
vector<pair<ll, ll>> point;
for (ll i = 2; i < n; i++) {
for (ll j = 2; j < m; j++) {
if (grid[i][j] == '+' &&
grid[i][j + 1] == '+' && grid[i][j - 1] == '+' &&
grid[i - 1][j] == '+' && grid[i + 1][j] == '+') {
point.emplace_back(i, j);
}
}
}
if (point.empty()) {
cout << 1 << endl;
return;
}
ll mx = -1;
ll pmx = (min(n, m) * 2) - 1;
for (auto &p : point) {
ll f = p.first;
ll s = p.second;
ll c = 0;
ll x = 1;
while (f + x <= n && f - x >= 1 &&
s + x <= m && s - x >= 1 &&
grid[f + x][s] == '+' && grid[f - x][s] == '+' &&
grid[f][s + x] == '+' && grid[f][s - x] == '+') {
c++;
x++;
}
mx = max(mx, ((4 * c) + 1));
if (mx == pmx) {
cout << mx << endl;
return;
}
}
cout << mx << endl;
}
int main() {
ALLAHU_AKBAR
ll t;
cin >> t;
while (t--) {
sir();
}
return 0;
}