This has happened to me twice now.
Every freeze, I can mouse over either deck and get a side image of cards in the deck.

First time
Monday Sept 14
about 10:30 - 11:00 PM EST
Zaladar 1-4 vs AI Lance
I finish my Turn 6 then End. Match freezes on Lance Turn 7.

Bug - Zal 1-4 vs Lan T7 stuck see deck cards 1.jpg
Bug - Zal 1-4 vs Lan T7 stuck see deck cards 2.jpg
Bug - Zal 1-4 vs Lan T7 stuck see deck cards 3.jpg

Second Time:
Wednesday Sept 16
about 3:20 - 3:50 AM EST
Ter Adun 1-1 vs AI Lance
I finish my Turn 6 then End. Match freezes on Lance Turn 7.

Bug - Ter 1-1 vs Lan T7 stuck see deck cards 1.jpg