@OlivierPS: you could try this:
/*============bigger link popup preview ================*/
.popover.hover-popover {
position: absolute;
z-index: var(--layer-popover);
transform: scale(0.9); /* makes the content smaller */
max-height: 800px; /* was 300 */
min-height: 100px;
width: 500px; /* was 400 */
overflow: hidden;
padding: 0;
border-bottom: none;
}
/* I'm not sure what this does, got popove code from Obsdn-Dark-Rmx */
/*
.popover {
background-color: var(--background-primary);
border: 1px solid var(--background-primary-alt);
box-shadow: 3px 3px 7px var(--background-modifier-box-shadow);
border-radius: 6px;
padding: 15px 20px 10px 20px;
position: relative;
}
There are plenty more other tweaks where this comes from.