Update Manager shows fewer updates on first load than after manual refresh

[Drako101]

Describe the bug
Update Manager shows fewer updates on first load than after manual refresh.

To Reproduce

1. Open Update Manager
2. Note the number of updates shown (6 updates appeared)
3. Click Refresh
4. More updates appear that were not visible before (8 updates appeared)

Expected behavior
All available updates should be shown on first load without needing to manually refresh.

Distribution:

• Linux Mint

Software version:
mintupdate 7.1.4

Logs:
2026.03.16@17:53 ++ Launching Update Manager
2026.03.16@17:53 ++ Inhibited power management
2026.03.16@17:53 ++ Checking for updates
2026.03.16@17:53 ++ Found 8 software updates
2026.03.16@17:53 ++ Refresh finished
2026.03.16@17:53 ++ Resumed power management

Additional context
On first load, only 6 updates were shown. After clicking Refresh, 2 additional updates appeared. This happens consistently on every launch, including on startup.

• Linux Mint: 22.3
• Cinnamon: 6.6.7