I had decided on building a gold farm but at the kind of test, I discovered that the cactus wasn't even hurting the zombie pigmen, but then I discovered that every mob and even players could walk and jump on it. Only on the sides can you and mobs be damaged and killed. Please, please, please fix this! I spent three days on this project.
Thank you for your report!
We're actually already tracking this issue at MCPE-14303, so we will resolve and link this ticket as a duplicate.
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