The bug
When you setting your graphic to Fabulous, Enchanted effect doesn't rendered properly but not on Fancy graphic.
And for Glass Block, it seems enchanted effect disappeared on Fabulous setting.
Reproduction steps
Change the graphics settings to "Fabulous!"
Give yourself an enchanted transparent block item
/give @s slime_block{Enchantments:[{id:power,lvl:1s}]}
/give @s glass{Enchantments:[{id:power,lvl:1s}]}
Throw the item on the ground
This still happens in 20w27a?