#include <bits/stdc++.h>
using namespace std;

int solve()
{
    int n, m;
    cin >> n >> m;
    vector<string> a(n);
    for (int i = 0; i < n; i++)
    {
        cin >> a[i];
    }
    vector<vector<pair<int, int>>> x(n, vector<pair<int, int>>(m));
    auto y = x;
    priority_queue<int> x_mx, y_mx;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            if (a[i][j] == '.')
            {
                int r = j;
                while (r < m && a[i][r] == '.')
                {
                    r++;
                }
                x_mx.emplace(r - j);
                r--;
                for (int l = j; l <= r; l++)
                {
                    x[i][l].first = l - j;
                    x[i][l].second = r - l;
                }
                j = r;
            }
        }
    }
    for (int j = 0; j < m; j++)
    {
        for (int i = 0; i < n; i++)
        {
            if (a[i][j] == '.')
            {
                int r = i;
                while (r < n && a[r][j] == '.')
                {
                    r++;
                }
                y_mx.emplace(r - i);
                r--;
                for (int l = i; l <= r; l++)
                {
                    y[l][j].first = l - i;
                    y[l][j].second = r - l;
                }
                i = r;
            }
        }
    }
    x_mx.emplace(0), x_mx.emplace(0);
    y_mx.emplace(0), y_mx.emplace(0);

    int ans = 0;
    {
        int t = 0;
        t += x_mx.top();
        x_mx.pop();
        t += x_mx.top();
        ans = max(ans, t);
    }
    {
        int t = 0;
        t += y_mx.top();
        y_mx.pop();
        t += y_mx.top();
        ans = max(ans, t);
    }
    priority_queue<int> q;
    q.emplace(0);
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            if (a[i][j] == '.')
            {
                ans = max(ans, y[i][j].second + q.top() + 1);
                ans = max(ans, y[i][j].second + 1 + x[i][j].first);
                q.push(x[i][j].first + 1);
            }
        }
    }
    while (!q.empty())
    {
        q.pop();
    }
    q.emplace(0);
    for (int j = m - 1; j >= 0; j--)
    {
        for (int i = 0; i < n; i++)
        {
            if (a[i][j] == '.')
            {
                ans = max(ans, x[i][j].first + q.top() + 1);
                ans = max(ans, y[i][j].first + 1 + x[i][j].first);
                q.push(y[i][j].first + 1);
            }
        }
    }
    while (!q.empty())
    {
        q.pop();
    }
    q.emplace(0);
    for (int i = n - 1; i >= 0; i--)
    {
        for (int j = m - 1; j >= 0; j--)
        {
            if (a[i][j] == '.')
            {
                ans = max(ans, y[i][j].first + q.top() + 1);
                ans = max(ans, y[i][j].first + 1 + x[i][j].second);
                q.push(x[i][j].second + 1);
            }
        }
    }
    while (!q.empty())
    {
        q.pop();
    }
    q.emplace(0);
    for (int j = 0; j < m; j++)
    {
        for (int i = n - 1; i >= 0; i--)
        {
            if (a[i][j] == '.')
            {
                ans = max(ans, x[i][j].second + q.top() + 1);
                ans = max(ans, x[i][j].second + 1 + y[i][j].second);
                q.push(y[i][j].second + 1);
            }
        }
    }

    cout << ans << "\n";
    return 0;
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int test = 1;
    cin >> test;
    while (test--)
    {
        solve();
    }
}