Auto-backup on save breaks KeePassRPC connection

[badjules]

Description:
I encountered an issue when using KPSimpleBackup, KeePassRPC, and the Kee browser plugin together.

🧩 Problem:
When the "Backup Database on Save" option in KPSimpleBackup is enabled, the following occurs:
After saving the KeePass database (e.g., after editing an entry), the browser plugin no longer displays any passwords.
The Kee browser extension (e.g., in Firefox) seems to lose connection to the database or can no longer access it.
The issue persists until KeePass is restarted.

🔁 Steps to Reproduce:
Open KeePass with the listed plugins enabled.
In KPSimpleBackup settings, enable "Backup Database on Save".
Modify an entry and save the database.
Visit a known login page in the browser.
No password suggestions are shown in the Kee plugin.
Restart KeePass – the plugin works again as expected.

✅ Expected Behavior:
After saving the database (and creating a backup), Kee should stay connected and continue to provide password suggestions without requiring a KeePass restart.

💻 System Information:
KeePass: 2.58 (64-bit) (Portable)
OS: Windows 10 x64

Plugins:
KPSimpleBackup 1.4.0
KeePassRPC 2.0.2.0
KeeOtp2 1.6.0.0
KeeResize 1.13.0.0

Browser:
Firefox Portable 138.0.1 (64-bit)
Kee (browser extension): 4.0.7

[dp-unkn]

I confirm such behavior. This happens in ANY browser which connected to KeePass. As I can see, the problem is, KPSB in some way "switching" to the newly backed up DB instead of main one. If you click on RPC plugin icon in your browser you may see other DB currently active instead of main.

[badjules]

I've confirmed that this issue only occurs when the "Backup Database on Save" option is enabled. In that case, KeePassRPC (and the Kee browser extension) lose connection after saving the database. Everything works again after restarting KeePass.

However, if I disable that option and instead perform a manual backup using the plugin, the connection remains completely stable, and no issues occur.

This strongly suggests that the problem is caused by a bug in the automatic backup logic – likely the backup file is mistakenly set as the active database. This should be fixable by ensuring that the original database remains active after saving and backing up.