When placing a torch on a cobblestone wall in the past, the wall would change to a pillar (like how it is at the corners of a wall) so that the torch is touching the wall. However, it no longer does this and now the torches are floating above the wall unless you place them at a corner piece
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We're actually already tracking this issue at MCPE-65404, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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