When placing a trapdoor on a block as shown in the screenshots and activate it while standing in the location it will cause you to start doing the swimming animation.
Linked issues
Attachments
Comments
No comments.
MC-148483
Trapdoors can cause swimming effect
Resolved
Duplicate
0
Sanjay Rajamohan
(Unassigned)
Unconfirmed
(Unassigned)
Minecraft 1.14 Pre-Release 3
Retrieved