Acts as an acyl-protein thioesterase that hydrolyzes fatty acids from acylated residues in proteins (PubMed:31740833). Regulates the mitochondrial S-depalmitoylation of the nucleophilic active site residue of peroxiredoxin-5/PRDX5, a key antioxidant protein, therefore modulating mitochondrial antioxidant ability (PubMed:31740833). Also catalyzes the deglucuronidation of mycophenolic acid acyl-glucuronide, an active metabolite of the immunosuppressant drug mycophenolate (PubMed:22294686).