Across:
8 Rotten (OFF-) bad habit (vice) doesn’t start (v) (‘vice’ without ‘v’ = -ICE) (OFFICE) in the workplace (OFFICE),
9 Perform with a choir (S-ING) going around popular (-HIP-) port (-P-) (SHIPPING) or going through the Panama Canal, for example (SHIPPING),
10 Some forthcoming amendment (some “forthcoming amendment” = GAME) could be a distraction (GAME),
11 Locate tree (locate tree = ELECTORATE) chopped up (= anagram indicator) by one possibly preparing to change what’s going into the house (ELECTORATE),
12 Strip poker removes kits (‘strip poker’ removes ‘kits’ = rppoer = PROPER) – how is that ladylike? (PROPER),
14 Poorest (poorest = -OORSTEP) cook (= anagram indicator) follows (= positional indicator) starter of dips (starter of ‘dips’ = D-) (DOORSTEP) with large slice of bread? (DOORSTEP),
15 Almost (n) assumed (‘given’ without ‘n’ = GIVE) most of them (most of ‘them’ = THE) in 10 across (‘game’ = GAME) and 24 across (‘away’ = AWAY) (GIVE THE GAME AWAY) let the cat out of the bag (GIVE THE GAME AWAY),
18 Old political leader from New York (DE VALERA was born in New York) with model (= anagram indicator) raved (raved = DE V-RA) about beer (-ALE-) (DE VALERA),
20 Sorry (RUEFUL) – this isn’t a reference to the local chipper? (local ‘chipper’ = ‘cheerful’ and not RUEFUL),
22 Mouthy type (TOOTH-) born (-B-) in north county Dublin (-RUSH) (TOOTHBRUSH) works as a dental cleaner (TOOTHBRUSH),
24 A (A-) course (-WAY) (AWAY) for getting out of the house (AWAY),
25 Claret (BLOOD RED) produced by the family (BLOOD) is a type of wine (RED wine) (BLOOD RED),
26 Knocks over (= reversal indicator) container (pan = NAP-) with the French (the = -LES) (NAPLES) port (NAPLES).
Down:
1 A (A-) party (Fianna Fáil = -FF-) broadcast (-AIR) (AFFAIR) leads to potential scandal (AFFAIR),
2 Footage (SIZE) of zombies getting rid of mob (‘zombies’ getting rid of ‘mob’ = zies = SIZE),
3 Groundwork (RESEARCH) for showing off (= anagram indicator) cars here (car here = RESEARCH),
4 Clare, for one (Clare Island = ISLE), immersed in tennis lesson (immersed in ‘tennis lesson’ = ISLE),
5 Open bar (open ‘bar’ = B-) to begin with (first = 1ST = -IST-) for most of (d) the staff (‘rod’ without ‘d’ = -RO) (BISTRO) in small restaurant (BISTRO),
6 Reviews the play (SPORTS PAGE) produced by the journalists working on The Courts (journalists working on the tennis courts / SPORTS PAGE),
7 American (A-) rewrites (= anagram indicator) anthem (anthem = -NATHEM-) – it’s a (-A) (ANATHEMA) thing of loathing (ANATHEMA),
13 Run a poetic (run a poetic = PRECAUTION) struggle (= anagram indicator) for The Backstop? (PRECAUTION),
14 Blind faith (DOGMA) in removing Renoir from reading room (removing ‘Renoir’ from ‘reading room’ = adgom = DOGMA),
16 Diamonds (ICE) and local money (LOLLY) (ICE LOLLY) appeals to sucker (ICE LOLLY),
17 Dealer (MERCHANT) finishes off (c) small car (Mercedes = ‘merc’ without ‘c’ = MER-) for a song (-CHANT) (MERCHANT),
19 English (E-) maiden (-M-) is all over Ash (-BARK is all over ash tree) (EMBARK) to go on board (EMBARK),
21 Accepted conventions (USAGES) in America (USA-) ends appalling practice nowadays (ends ‘appalling practice nowadays’ = -GES) (USAGES),
23 Old city (UR-) of the French (French ‘of’ = -DU) (URDU), in a manner of speaking (URDU),
24 Past master has no treats (‘past master’ has no ‘treats’ = pams = AMPS) for the musicians (AMPS).