Dear expert I found a issue when setting format in SharePoint List via Json Error: ref '/properties/attributes/class' in 'https://developer.microsoft.com/json-schemas/sp/v2/column-formatting.schema.json' can not be resolved.(768) The URL is correct, but why there is an error?
JSON does not hide choice options correctly in a SharePoint online list

I've a Choice column in a SharePoint online list. The column contains 19 values, of which the first 6 are still active. The values that are deprecated cannot be deleted. As text and script editor web parts are blocked in my environment, I want to hide every choice but the first 6:
Culture & Empowerment, Gigabit Network, Digital Ecosystems, Society & Sustainability, Customer Experience, Grow Profitability.
The JSON code I use seems correct to me, but it's buggy: 2 choices are not visible, some choices suddenly show twice in the list and some of the deprectated items are shown.
This is the code I used:
{
"$schema": "https://developer.microsoft.com/json-schemas/sp/v2/column-formatting.schema.json",
"elmType": "div",
"attributes": {
"class": "sp-field-custom-format"
},
"children": [
{
"elmType": "span",
"txtContent": "[$Theme]"
}
],
"style": {
"display": "=if@currentField == 'Culture & Empowerment' || @currentField == 'Gigabit network' || @currentField == 'Digital Ecosystems' || @currentField == 'Society & Sustainability' || @currentField == 'Customer Experience' || @currentField == 'Grow Profitability', 'block, 'none')"
}
}
Can anyone help me out?