SFC-state container has description:
description
"This containers holds operational service function
chain state and their associated service path";

YANGUI: YANGUI_ERROR_GET_404 - : Request could not be completed because the relevant data model content does not exist

BUT:
/restconf/operational/service-function-path:service-function-paths-state

{
"service-function-paths-state": {
"service-function-path-state": [
{
"name": "SFCGBP-Path",
"sfp-rendered-service-path": [

{ "name": "SFCGBP-Path-RSP-Reverse" }

,

{ "name": "SFCGBP-Path-RSP" }

]
}
]
}
}

and
/restconf/config/service-function-chain:service-function-chains
{
"service-function-chains": {
"service-function-chain": [
{
"name": "SFCGBP",
"symmetric": true,
"sfc-service-function": [

{ "name": "firewall-abstract1", "type": "service-function-type:firewall" }

,

{ "name": "dpi-abstract1", "type": "service-function-type:dpi" }

]
}
]
}
}

Unless there is a specific feature on the Be release plan for this container it should be deleted as it appears to not be used or useful.