Weirdly the AdGuard Tracking Protection filter has a cosmetic rule that is blocking the images.

If I'm understanding the syntax correctly it seems to be this one.

    ~underverse.su,~underver.se,~minu.stv.ee,~sota.com,~7kingdoms.ru,~epicl2.com,~forum.ixbt.com,~forum.themega.ru,~gamepedia.com,~makeserver.ru,~mozhor.ru,~onliner.by,~wiktionary.org,~yandex.by,~yandex.com,~yandex.com.tr,~yandex.ru,~yandex.ua##img[width="88"][height="31"]

The comment says the intent is to hide hit counters.