Abra uses the new address format (Cash Addresses or Q Addresses) for Bitcoin Cash (BCH) wallets.
The change in address format was done by the Bitcoin Cash (BCH) development team to prevent users from sending Bitcoin (BTC) funds to Bitcoin Cash (BCH) wallets and vice versa, since both the coins had the same address format until the recent change by Bitcoin Cash (BCH). For more information regarding the change, click here.
Any wallet which currently does not support the new address format can still send funds to the new address format wallets by obtaining the legacy address from the cash address using a simple address converter tool: https://cashaddr.bitcoincash.org/
Please note, when withdrawing BCH from one Abra wallet to another the BCH QR code scanner will work without issue, but to an external address you will need to manually add "bitcoincash:" at the beginning of the address.