The bug:
Vines and glow lichen take longer to break when connected to the side of an opened shulker box compared to other blocks like torches.
Also, glow lichen and vines will not break after opening shulker boxes when placed on their lid.
Expected behavior:
Vines and glow lichen break at the same time as torches, buttons, etc. when they're on the side of an opened shulker box.
Vines and glow lichen will break if they're on the lid of an opened shulker box.
This issue also affects sculk veins; I've updated this ticket accordingly and made some minor changes so it's easy to understand the problem here at an initial glance.