.cms table.ss-gridfield-table tr td.gridfield-preview{
    padding-top: 0;
    padding-bottom: 0;
}
.cms table.ss-gridfield-table .ss-gridfield-sorting .dataobjectpreview{
    display: none;
}
.cms table.ss-gridfield-table tr td.gridfield-preview{
    padding-top: 0;
    padding-bottom: 0;
}
.cms table.ss-gridfield-table .ss-gridfield-sorting .dataobjectpreview{
    display: none;
}

.cms table.ss-gridfield-table .dataobjectpreview {
    position: relative;
}

/* Overlay to make the iframe area clickable */
.cms table.ss-gridfield-table .dataobjectpreview:after {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    display: block;
    height: 100%;
    width: 100%;
}
Make iframe area in grid field clickable
Make iframe area in grid field clickable

The iframe was absorbing pointer events when moused over, which meant the
preview in grid fields could not be clicked to open a record.
