Are thumbnails too large?
/* ==UserStyle==
@name Small thumbnails
@version 5.0.0
@description Are thumbnails too large?
Gotcha.
@author Valognir (https://www.deviantart.com/valognir)
@namespace https://greasyfork.org/en/scripts/404192-small-thumbnails
==/UserStyle== */
@-moz-document domain("deviantart.com") {
div[data-testid="thumb"] > img {
scale: 70%;
}
}