Riding a minecart through portals with gamerule entitiesWithPassengersCanUsePortals true can cause the player and minecart to be offset from where the actual block is.  The offset is often greater than one block on both entities with the player sometimes being the only passenger offset from the minecart and the block 

A video is attached below showcasing the issue. 
https://youtu.be/xYZurtO-CQI