Across:
8 Endless (p) music (‘rap’ without ‘p’ = -RA-) in restaurant (CA-FE) (CARAFE) might be the choice of sommelier (CARAFE),
9 Tenor (T-) working The Streets’ musicians (‘The Streets’ are a rap group & musicians working on the streets describes rappers -RAPPING) (TRAPPING) is not releasing anything (TRAPPING),
10 Articles dismissing lice (‘articles’ dismissing ‘lice’ = arts = ARTS) studied by those in university (ARTS),
11 Promotion (COMMERCIAL) of unstable (= anagram indicator) comic realm (comic realm = COMMERCIAL),
12 Students of the past (ALUMNI) in old boys’ club (ALUMNI),
14 Producer (maker = MA- -KER) rings UK leader (Prime Minister = -P M-) and American leader (‘American’ leader = -A-) (MAP MAKER) sketching out how the world looks (MAP MAKER),
15 The Tailor of Panama (CENTRAL AMERICAN) got money (CENT-) by word of mouth (oral) starting off (o) (‘oral’ without ‘o’ = -RAL) from Hollywood, Los Angeles (AMERICAN) (CENTRAL AMERICAN),
18 Surprise (HO-) at Nora (-NORA-) and Regina (-R-) taking yard (-Y) (HONORARY) position that doesn’t pay (HONORARY),
20 Sip from glass? Pier (‘sip’ from ‘glass pier’ = glaser = LAGERS) offers drinks for those who like cold ones! (LAGERS),
22 Prefer (FAVOUR-) one (-I-) place (set), on reflection (= reverse indicator) (set = -TES) (FAVOURITES), for pets (FAVOURITES),
24 Found in Bluebell – a store (found in ‘bluebelL – A STore’ = LAST) that’s a model for the cobblers (shoemaker’s model for shaping/repairing = LAST),
25 Reading (from the 3Rs = R-) Euclid (Euclid = -ID-CULE) out (= anagram indicator) around island (-I-) (RIDICULE) leads to contempt (RIDICULE),
26 Sings the praises (EXTOLS) of former partner (EX-) lost (lost = -TOLS) at sea (= anagram indicator) (EXTOLS).
Down:
1 Crude container (BARREL) holding 20 across, for example (BARREL holding ‘lagers’),
2 Some of those raised in Baltinglass appreciated (some of those raised in ‘baltinglaSS APpreciated = ssap = PASS) by one of those in the mountains (PASS),
3 Colourful types of dishes (RED CHINA) produced by old cold war country (RED CHINA),
4 Check (STEM) both sides of Stewart’s Theorem (both sides of ‘STewart’s theorEM’ = STEM),
5 Local is jumping for joy (‘locally’ jumping for joy = MADE UP), as it’s not true (MADE UP),
6 Keeping an eye on (SPECTATING) what The Observer is doing (SPECTATING),
7 American (American) model (= anagram indicator) (American = IN CAMERA) found in the Roman chamber of The Court (IN CAMERA),
13 Subway (METRO-) synonymous with Greek city (-POLIS) (METROPOLIS) – the state capital perhaps (METROPOLIS),
14 Substantial food for thought (MEATY) for Turkey (MEAT-) and leader of Yemen (leader of ‘Yemen’ = -Y) (MEATY),
16 Sweetheart (‘swEet’ heart = E-) nearly (t) got (‘got’ without ‘t’ = -GO-) craving (-MANIA) (EGOMANIA) for what the diva has (EGOMANIA),
17 Eldest in (eldest in) trouble (= anagram indicator) (eldest in = ENLISTED) took a job with a major employer (ENLISTED),
19 It’s traumatic losing cat (‘traumatic’ losing ‘cat’ = traumi = ATRIUM) from open courtyard (open courtyard/atrium = ATRIUM),
21 Take is easy (rest = RES-T) around university (University of Limerick/ UL = -UL-) (RESULT) with Mark (mark in an exam/ result = RESULT),
23 It’s sentimental (TWEE) to most of (t) Twitter (‘tweet’ without ‘t’ = TWEE),
24 Gives the green light to (allows = LETS) reviewing (= reverse indicator) segments of The Waste Land (segments of ‘the waSTE Land’ = stel = LETS).