Tabulator: Column-Group-Header & Column-Header Context Menus - tabulator

Question

I have recently upgraded Tabulator from 4.9 to 5.1.7.
I have a table that defines headerContextMenus for both Column-Group-Headers & Column-Headers.
I am seeing that the headerContextMenu for Column-Group-Headers is being applied to the Column-Group-Header (correct) & the Column-Header (incorrect).
I am also seeing that the headerContextMenu for Column-Headers is being ignored.
This used to work in version 4.9.
My column definitions are shown below and look OK to me.
Are there changes in this area that perhaps are not yet covered in the docs?
let tableColumns = [
{
"title": "Metric",
"field": "metricName",
"frozen": true,
"visible": true,
"headerSort": false
},
{
"title": "HierProj.SP5.dhm.styson.baseline_0 (BASELINE:dhm)",
"headerContextMenu": [
{
"label": "Set baseline"
}
],
"columns": [
{
"title": "320_fc_synpnr.020_compile.compile",
"field": "HierProj^SP5^dhm^styson^baseline_0320_fc_synpnr^020_compile^compile",
"visible": true,
"headerSort": false,
"headerContextMenu": [
{
"label": "Hide checkpoint"
}
],
"contextMenu": [
{
"label": "Open image in new tab"
}
]
}
]
},
{
"title": "HierProj.SP5.dhm.styson.timing_0",
"headerContextMenu": [
{
"label": "Set baseline"
}
],
"columns": [
{
"title": "320_fc_synpnr.020_compile.compile",
"field": "HierProj^SP5^dhm^styson^timing_0320_fc_synpnr^020_compile^compile",
"visible": true,
"headerSort": false,
"headerContextMenu": [
{
"label": "Hide checkpoint"
}
],
"contextMenu": [
{
"label": "Open image in new tab"
}
]
}
]
},
{
"title": "HierProj.SP5.dhm.styson.power_0",
"headerContextMenu": [
{
"label": "Set baseline"
}
],
"columns": [
{
"title": "320_fc_synpnr.020_compile.compile",
"field": "HierProj^SP5^dhm^styson^power_0320_fc_synpnr^020_compile^compile",
"visible": true,
"headerSort": false,
"headerContextMenu": [
{
"label": "Hide checkpoint"
}
],
"contextMenu": [
{
"label": "Open image in new tab"
}
]
}
]
}
]