Glyceryl-ether monooxygenase that cleaves the O-alkyl bond of ether lipids. Ether lipids are essential components of brain membranes (By similarity). (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + 1-O-(1,2-saturated-alkyl)-sn-glycerol + O2 = (6R)-L-erythro-6,7-dihydrobiopterin + a 1-(1-hydroxyalkyl)-sn-glycerol + H2O Belongs to the sterol desaturase family. TMEM195 subfamily.