When I opened the creative inventory screen (potions), my fps dropped from about 25 fps to 8 fps.
When looking in the sky, my fps was 61 dropped to about 9
Linked issues
is duplicated by 7
MC-57817
Item enchant effect make fps dropped
Resolved
MC-64343
Potions cause massive framerate drop
Resolved
MC-64603
Significant frame rate drop while browsing potions in creative inventory.
Resolved
MC-65109
Enchanting effect in inventory menu lags the game
Resolved
MC-65185
Items in inventory, as well as item drops, greatly decrease FPS
Resolved
2 more links
I've experienced this as well!