[Resolved] Cannot use object of type WP_Term as array in

Hello,

Thanks for the feedback!

It looks like the issue come from the ACFML source code here, as suggests the error message. In fact, in the ACFML code /acfml/classes/strategy/repeater-shuffle/OptionsPage.php line:89, WPML does the following conditional to check the value during their save logic:

if ( $value instanceof \WP_Post || isset( $value['ID'] ) ) {
However, in the case of the ACFE Taxonomy Terms field, the $value here is a WP_Term object, so the first condition is not met. Then the code try the other condition: isset( $value['ID'] ), but it doesn't doesn't check if $value is an array before trying to accessing the ID key, and since the value is an object, PHP throws an error.

By the way, that same error can be reproduced with ACF Pro only (without ACF Extended), using the native ACF Taxonomy Field displayed as "Select" and with a "Return Format: Term Object". This is because the ACFML code logic rely on get_fields() line:72 with format_value = true, which means all values will be formatted as in the Field UI Settings (see documentation). I wouldn't recommend to enable the format_value in get_fields() so the logic can assume that it will always retrieve raw database data.

I would recommend to contact the WPML support to let them know.

Here is the Field Group json of a native ACF Taxonomy Field (without ACF Extended) producing the same issue, if you want to test it:

[
    {
        "key": "group_642182b1190c4",
        "title": "My Options Page",
        "fields": [
            {
                "key": "field_642184bf457ea",
                "label": "Taxonomy",
                "name": "taxonomy",
                "aria-label": "",
                "type": "taxonomy",
                "instructions": "",
                "required": 0,
                "conditional_logic": 0,
                "wrapper": {
                    "width": "",
                    "class": "",
                    "id": ""
                },
                "wpml_cf_preferences": 3,
                "acfe_save_meta": 0,
                "taxonomy": "category",
                "add_term": 0,
                "save_terms": 0,
                "load_terms": 0,
                "return_format": "object",
                "field_type": "select",
                "allow_null": 0,
                "multiple": 0,
                "min": "",
                "max": ""
            }
        ],
        "location": [
            [
                {
                    "param": "options_page",
                    "operator": "==",
                    "value": "my-options-page"
                }
            ]
        ],
        "menu_order": 0,
        "position": "normal",
        "style": "default",
        "label_placement": "left",
        "instruction_placement": "label",
        "hide_on_screen": "",
        "active": true,
        "description": "",
        "show_in_rest": 0,
        "acfml_field_group_mode": "localization",
    }
]
Hope it helps!

Have a nice day!

Regards.