fix key press on windows activated

src/main.cpp

@@ -828,6 +828,21 @@ LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, WPARAM wp, LPARAM lp)
         tasklist.emplace_back([=] {
             int active = GET_WM_ACTIVATE_STATE(wp, lp);
             WacomTablet::I.set_focus(active);
+            for (int k = 0; k < 256; k++)
+            {
+                if (App::I.keys[k])
+                {
+                    for (int i = 0; i < 256; i++)
+                    {
+                        if ((int)convert_key(i) == k)
+                        {
+                            bool down = GetKeyState(i) & 0x8000;
+                            if (!down)
+                                App::I.key_up((kKey)k);
+                        }
+                    }
+                }
+            }
         });
         break;
     }