Troubleshooting Tip: Firmware Template Warning Message 'Please note this is not a recommended upgrade path'

When trying to upgrade FortiGate using a firmware template in FortiManager, in the upgrade path preview, a warning message appears saying 'Please note that this is not a recommended upgrade path', even though the upgrade path is normal.

Check on FortiManager CLI, no errors observed, and CLI shows correct upgrade path without any warning:

FMG # diagnose fwmanager show-dev-upgrade-path
<devname> device name. Available:
FG200E-1 (id:770, version:7.0.15-632)
FortiGate-B (id:201, version:7.0.17-287)(offline)
FortiGate-6-2 (id:253, version:7.2.11-1740)

FMG # diagnose fwmanager show-dev-upgrade-path FG200E-1 7.2.11
FG200E-1(770): ->7.2.10-b1706-M ->7.2.11-b1740-M

Note:

This issue is identified under the Known Issue ID 1117810, and the issue is planned to be resolved in v7.4.8 and v7.6.4.