When blocking with shield, shulkers and strays are able to give the player a potion effect. Example: If a shulkers bullet hits a player while a shield is raised the player would still get the levitation effect even when the play has blocked the attack of a shulkers, same applies to strays when a stray shoots a player with a raised shield, a player would still get the slowness effect even when the player was blocking a stray attack
Thank you for your report!
We're actually already tracking this issue at MCPE-52904, 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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