Java Edition:Unconnected Dripleaf Stem
The dripleaf plant is supposed to end with a big dripleaf, and will normally break when it's removed. However, from 21w06a to 21w16a, breaking the dripleaf doesn't cause the stem to break.
Obtaining
Breaking Big Dripleaf
From 21w06a to 21w16a, the big dripleaf could be broken without making the whole plant break. Updating the unconnected stem in future versions will cause it to break.
Update Suppression
While much more difficult, update suppression can also be used to recreate unconnected dripleaf stem in earlier and later versions.