Image metadata / "Copyright Info URL" field uneditable

That's curious... Additionally, Bridge and Photoshop should be the same. As a workaround, you can try this script.

#target photoshop

// Create dialog window
var dlg = new Window('dialog', 'Set Copyright Info URL');
dlg.orientation = 'column';
dlg.alignChildren = 'fill';

// Group for label and edittext
var urlGroup = dlg.add('group');
urlGroup.orientation = 'row';
urlGroup.add('statictext', undefined, 'URL:');
var urlInput = urlGroup.add('edittext', undefined, '');
urlInput.characters = 30;

// OK and Cancel buttons
var btnGroup = dlg.add('group');
btnGroup.alignment = 'right';
var cancelBtn = btnGroup.add('button', undefined, 'Cancel');
var okBtn = btnGroup.add('button', undefined, 'OK');

okBtn.onClick = function () {
    var url = urlInput.text;
    dlg.close();
    set(url);
};

cancelBtn.onClick = function () {
    dlg.close();
};

dlg.center();
dlg.show();

function set(URL) {
    var s2t = function (s) {
        return app.stringIDToTypeID(s);
    };
    var descriptor = new ActionDescriptor();
    var descriptor2 = new ActionDescriptor();
    var reference = new ActionReference();
    reference.putProperty(s2t("property"), s2t("fileInfo"));
    reference.putEnumerated(s2t("document"), s2t("ordinal"), s2t("targetEnum"));
    descriptor.putReference(s2t("null"), reference);
    descriptor2.putString(s2t("URL"), URL);
    descriptor.putObject(s2t("to"), s2t("fileInfo"), descriptor2);
    executeAction(s2t("set"), descriptor, DialogModes.NO);
}

https://prepression.blogspot.com/2017/11/downloading-and-installing-adobe-scripts.html