I just searched through about 20 different pages of posts, looking for mention of the armrests in row 18. Only one post said they were not, others referred to the old cabin seating and one mentioned row 30.

So I looked at the AC Fleet pages.

Interestingly, on the 788 and 789 page, this info (image 1) appears at the bottom, but of the 777-200LR (image 2) and for the 777-300ER (image 3), the info is different.

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