After update to v39 on Android, if I tap on the costume hero at war field on ally defence team (to see stats), game will crash immediately. I can reproduce 100% at least with Karil-cos, Kadilen-cos. However. Elena-cos is a safe so not 100% of costumed heroes.
It only happened on war field with costumed hero, not with non-costume heroes nor regular hero roster or raid. I checked with Android 7 and Android 11 and both have same issues. A friend in my alliance has same issues with his Android 8.