Speed tradeoff for when to show a file as a thumbnail. If set to "always" then always thumbnail, even if the folder is on a remote server. If set to "local-only" then only show thumbnails for local file systems. If set to "never" then never bother to thumbnail files, just use a generic icon. Despite what the name may suggest, this applies to any previewable file type.
Wisselsjnelheid veur wienie ein aafbiljing te tuine es verkleinde weergaaf. Ingeval "ummer" weurt 't ummer verkleind getuind, ouch wen 't op ein server-op-aafsjtandj is. Ingeval "allein_lokaal" weurt 't allein verkleind getuind op 't lokale systeem. Ingeval "noets" weurt 't noets verkleind getuind, zjus ein algemein plaetje.