When using a KDBX 4 DB (Argon2 or AES-KDF does not matter), Yubikey auth can be removed by editing and saving an entry, while the Yubikey is unplugged.

Expected Behavior

Similar to KDBX 3.1 an error message should be displayed when the Yubikey is unplugged.

Current Behavior

The database is saved with challenge-response disabled.

Steps to Reproduce (for bugs)

1. Create a new DB, with password and challenge-response
2. Create e new entry and save
3. Change key derivation function to KDBX 4 (does not matter whether Argon2 or AES-KDF is used)
4. Unplug Yubikey
5. Open entry, change password
6. Save entry
7. Close DB
8. Open DB with password only

Debug Info

KeePassXC - Version 2.3.0
Revision: 4c0ed74

Libraries:

• Qt 5.10.1
• libgcrypt 1.8.2

Operating system: Arch Linux
CPU architecture: x86_64
Kernel: linux 4.15.6-1-ARCH

Enabled extensions:

• Auto-Type
• Browser Integration
• Legacy Browser Integration (KeePassHTTP)
• SSH Agent
• YubiKey