Try adding widgets on the main screen
Widgets can not be added, although I have tried to add them repeatedly. And I uninstalled the app and then reinstalled it. But the same problem still occurs.
Install the latest version of Xabber app, then open and run the app. Once you have successfully entered into the application. Then you have to add widgets on the main screen, then you will find the problem as I have explained, that widget can not be added.