It appears that candles which have recently been added to bedrock edition are incapable of being placed on half slabs and stairs. They are capable of existing on them if you place them on a full block then replace the full block with a half slab or stair block. This is just slightly annoying but hopefully can be fixed soon. good luck with 1.18 and thanks for making a great game.
MCPE-145285
candles can't be placed on half slabs or stairs on bedrock edition.
Resolved
Duplicate
0
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We're tracking this issue in MCPE-130695, so this ticket is being resolved and linked as a duplicate.
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