Whenever you hold a barrier block and looking trough it, the rendering of translucent blocks behind the barrier block glitch, either its flashing or being on top of the barrier particle/block, this occurs with pretty much every translucent block like glass, trapdoors, doors, iron bars and much more, the glitch is more noticeable with trapdoors or iron bars.
this is purely a visual glitch but its pretty annoying
This issue has already been reported. Duplicate MCPE-116766 and MCPE-116767.
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