Unclued lights, all confirmed in Chambers or Collins, are three sets of four words of a kind, each set relating differently to a theme word which must be shaded in the completed grid.
 

Across

11    Religious devotee keeping a church in shade (6)
12    Sloth in tangles in New Zealand trees (6)
13    Country moving forward area for us in Jamaica (5, doubly hyphened)
17    Muppet grabbed by squirrel-monkey (4)
18    Physicist’s ally, one protecting university (5)
19    Ending operation led by twit (7)
23    Message from paperweight? (8)
24    Recent clothing still a youngster’s outfit (7)
25    A bit downcast, I jeer about fools (6)
30    Record one banal bit...