Made notifications work again, activation doesn't work yet due to missing ToastActivatorCLSID on the shortcut.

GreenshotWin10Plugin/Native/Structs/NotificationUserInputData.cs

@@ -0,0 +1,30 @@
+// ******************************************************************
+// Copyright (c) Microsoft. All rights reserved.
+// This code is licensed under the MIT License (MIT).
+// THE CODE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH
+// THE CODE OR THE USE OR OTHER DEALINGS IN THE CODE.
+// ******************************************************************
+
+using System;
+using System.Runtime.InteropServices;
+
+namespace GreenshotWin10Plugin.Native.Structs
+{
+    /// <summary>
+    /// See <a href="https://docs.microsoft.com/en-us/windows/win32/api/notificationactivationcallback/ns-notificationactivationcallback-notification_user_input_data">NOTIFICATION_USER_INPUT_DATA structure</a>
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential), Serializable]
+    public struct NotificationUserInputData
+    {
+        [MarshalAs(UnmanagedType.LPWStr)]
+        public string Key;
+
+        [MarshalAs(UnmanagedType.LPWStr)]
+        public string Value;
+    }
+}