Application crashes when a large volume of contacts are highlighted then added to the favorites list

Expected behavior

Clicking the favorites icon (star) when all the available contacts are selected and highlighted, should add them to the favorite list. Trying to continuously scroll down while this action is being processed should not crash the application.

Actual behavior

The application hangs, then crashes when there is a continuous attempt to scroll down while the contacts get added to favorites.

How to reproduce

• Download the app from fdroid store
• Scroll through your menu and launch app.
• Allow permissions when prompted
• Hold and select a contact
• Select all available contacts by clicking on the clustered square icon, the first of three icons on the top bar
• Then add these contacts to favorites by clicking on the star icon located between the square icon and the vertical dots.
• The app hangs, now continuously try scrolling down and the application crashes with an error message.

• Device: TECNO-L8Plus

• Operating system: Android 5.1

• Application: Simple Contacts

• version: 3.5.2

Recording Of The Bug