Sync not reliable when database uses yubikey and is used on two PCs at the same time

[liayn]

Overview

I'm using a database protected with a yubikey as additional factor.
The database is stored on OneDrive and hence shared between my Windows Laptop and Linux PC.

The database is usually open on both at the same time.

Changes are not synced properly and even led to a lost password after a manual DB merge.

Steps to Reproduce

1. Create a database protected with a yubikey and store it on a cloud storage (OneDrive in my case)
2. Open the database on first PC (yubikey must be present)
3. Open the database on second PC (yubikey moved to this PC)
4. Modify an entry on the second PC and save the database (yubikey must be present)
5. Watch KeepassXC on first PC trying to merge the changes due to the detected file change.
6. The merge fails due to missing yubikey
7. A red error box is shown briefly but vanishes
8. The database on first PC is marked as modified (* in the title bar)

Expected Behavior

KeePassXC should allow to retry the merge by providing an appropriate button when the initial sync fails in step 6

Put the user in charge of providing the yubikey and hitting the button.

Note: Using the menu option to merge databases by selecting the same database again does work somehow, but managed to actually dismiss changes that have been made on the second PC. Besides that, doing this manually every time is cumbersome.

KeePassXC should show what has been modified in the database somewhere

If a database is marked as modified, there should be an overview what's changed.
In my case above the database on the first PC was unmodified before the failed sync and shows as modified afterwards.
If one forgets to do a manual database merge and simply saves the database, one actually overrides all changes that should have been merged in from the file changed by the second PC. 🤨

Actual Behavior

Databases are not synced, due to missing yubikey.

Context

KeePassXC - Version 2.7.4
Revision: 63b2394

on both PCs

First PC:

Operating System: Windows 10

Second PC:

Operating System: Linux
Desktop Env: KDE
Windowing System: X11

[droidmonkey]

If you are using the same database protected by yubikey in two locations at the same time, then you need to buy another yubikey or remove that protection method. There is an open bug for the data loss issue that doesn't just impact yubikey, it's just more obvious for yubikey users across multiple devices. #5290

[liayn]

Thanks for the response and sorry for the duplicate.