Thank you for bring this to out attention. It seems that the new version of KnockoutJS (a library we use) may be incompatible with Opera Mobile Classic. Since we are not using any features from the new version of KnockoutJS (3.1) that were not present in the older version of KnockoutJS (2.2), we have reverted to version 2.2.
Let us know if this solves your issue and then we can close this ticket.