Cryptic crossword No 3,944

Across

1. Dictator's material in disputed region (7)
2. Who have nothing to go after - yippee! (7)
3. Mr Leo's magic mushrooms (6)
4. Stickler pleads regularly with social worker (6)
5. Timeless celebrities, topless, evoke Bloomsbury Group perhaps? (8)
6. 80s pop act featured in two consecutive articles (3,3)
7. See 20d
8. Banger from unknown Joplin remix - unfashionable but first class! (6)
9. Ice cultivated with solar energy (8)
10. American Rock & Roll act with a lazer and no drugs (8)
11. It's wrong and, on reflection, a bit much to sing like the Bee Gees (8)
12. Billy Jean possibly follows leads to big blues axeman (1,1,4)
13. Customers place books among Comic Section initially (7)
14. Course reportedly gets cut short by the German pilot (6)

Down

1. Dish all knocked back after split pea (6)
2. Coke agitates cons (6)
3. Adult toy broadcast on barrio TV! (8)
4. Article on congestion leads to group going underground (3,3)
5. See 13d
6. Pair of unknowns having shaved, stop 3 beards (1,1,3)
7. Heaven-bound rockers crushed pill - deep zen! (11)
8. Desperate character to acquire current rank - becoming more fastidious (8)
9. Kneecap's new LP - a steal! (8)
10. Primary focus of Government has eventually turned to overhaul area of urban poverty (6)
11. Ingredients for glycocoll are disposed of before getting nicked (8)
12. On outskirts of Baltimore, Republican heroes with no energy found naked - get dressed again (6)
13. No rest day after Bishop finds satanic band (12)
14. I see extracts from dashcam on a regular basis (3)
15. In Spain, carefully handle traditional organ music (6)
16. Out of sight, in Nice a Belgian male left with German (8)