Single Instance fix #3241

Fixes single instance depreciation

lib/main-app.js

@@ -5,24 +5,23 @@ const ipc = electron.ipcMain
 const GhReleases = require('electron-gh-releases')
 const { isPackaged } = app
 // electron.crashReporter.start()
+const singleInstance = app.requestSingleInstanceLock()
 
 var ipcServer = null
 
 var mainWindow = null
 
-var shouldQuit = app.makeSingleInstance(function (commandLine, workingDirectory) {
-  if (mainWindow) {
-    if (process.platform === 'win32') {
-      mainWindow.minimize()
-      mainWindow.restore()
-    }
-    mainWindow.focus()
-  }
-  return true
-})
-
-if (shouldQuit) {
+// Single Instance Lock
+if (!singleInstance) {
   app.quit()
+} else {
+  app.on('second-instance', () => {
+    // Someone tried to run a second instance, it should focus the existing instance.
+    if (mainWindow) {
+      if (!mainWindow.isVisible()) mainWindow.show()
+      mainWindow.focus()
+    }
+  })
 }
 
 var isUpdateReady = false