Spruce in 1.16.4 only grow 8 height rather than 9 in older version

in game behavior shows in pic

Here's part of code deobfuscated using yarn mapping (1.16.4)

by comparison, this part of code is from 1.15.2

This is a more detailed file containg codes related

part-1.txt

^{Edit: This bug affect all 1.16 subversions, not just 1.16.4.}