We cannot do the same by the standard as it is a limitation for custom records of multi-select type.
So we need to add a new formula HTML field of inline type with store value false and default value.
Then use the formula below.
<!DOCTYPE html>
<html lang=”en”>
<head>
<meta charset=”UTF-8″>
<meta name=”viewport” content=”width=device-width, initial-scale=1.0″>
<style>
.button {
text-decoration: none;
display: inline-block;
width: 30px; /* Size of the button based on the provided image */
height: 30px;
font-size: 20px; /* Font size for the plus sign */
font-weight: bold; /* Make the plus sign bold */
color: #3A5A98; /* Color of the plus sign */
background-color: transparent; /* Initially no background color */
border: none; /* Initially no border */
text-align: center;
line-height: 30px; /* Vertically center the plus sign */
border-radius: 5px;
transition: background-color 0.3s, border 0.3s; /* Smooth transition for background color and border */
}
.button:hover {
background-color: #f0f0f0; /* Light black (dark gray) background color when hovered */
border: 1px solid #3A5A98; /* Blue border color when hovered */
}
.button p {
margin: 0; /* Removes default margin from <p> tag */
}
</style>
</head>
<body>
<a href=”https://6768238.app.netsuite.com/app/common/custom/custrecordentry.nl?rectype=212&whence=”
class=”button”
target=”_blank”>
<p>+</p>
</a>
</body>
</html>