I'm not sure if this is a bug or an oversight but to my understanding glowsquids spawn in a water source with blocks above it. With that in mind I think it might be reasonable that the swamp tree is what caused it to spawn yet I'm not entirely sure.
[media]
MC-223213
Glow Squids Spawning in Swamps
Resolved
Duplicate
0
Jim Bo James
(Unassigned)
Unconfirmed
(Unassigned)
21w15a
Retrieved
Thank you for your report!
We're tracking this issue in MC-221571, so this ticket is being resolved and linked as a duplicate.
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