https://github.com/Unity-Technologies/UnityCsReference/blob/73f36bfe71b68d241a6802e0396dc6d6822cb520/Modules/TreeEditor/Includes/Perlin.cs#L180
"normalize2" and "normalize3" uses y value twice for the result

curently reads:
x = y / s;
y = y / s;
should read:
x = x / s;
y = y / s;

If the mentioned functions should follow common math terms, a normalization of n values should not copy a single result into all other results (like it currently does). Since these methods are used to calculate a seed for Perlin noise, the bug has no immediate effects but is probably affecting the noise distribution...