Enables ubiquitin-like protein-specific protease activity. Acts upstream of or within several processes, including nuclear speck organization; positive regulation of NLRP3 inflammasome complex assembly; and positive regulation of macromolecule metabolic process. Predicted to be active in several cellular components, including dendritic spine; midbody; and postsynaptic density. Predicted to be extrinsic component of endosome membrane and extrinsic component of plasma membrane. [provided by Alliance of Genome Resources, Apr 2022]