Clicking the title link in the list webpart opens two tabs

tom751000 

Usually, the list itself is configured to Open items in a new tab, no adding this code is actually asking it to open it twice.

try removing the "target": "_blank" attribute from the attributes section in the JSON code. This should make the button open the item in the same tab instead of opening a new tab.

Below is the modified JSON without the "target": "_blank" attribute, hopefully this works or leads you to a path where you can resolve this

{
    "$schema": "https://developer.microsoft.com/json-schemas/sp/v2/column-formatting.schema.json",
    "elmType": "button",
    "customRowAction": {
        "action": "defaultClick"
    },
    "attributes": {
        "title": "[$Title]",
        "data-interception": "off",
        "rel": "noopener noreferrer"
    },
    "style": {
        "border": "none",
        "background-color": "transparent",
        "cursor": "pointer"
    },
    "children": [
        {
            "elmType": "div",
            "txtContent": "[$Title]",
            "style": {
                "white-space": "nowrap",
                "text-overflow": "ellipsis",
                "overflow": "hidden",
                "font-size": "20px"
            }
        }
    ]
}