Transparency artifacts occur when multiple translucent surfaces are observed through one another

[japsuu]

Describe the bug
The current Weighted Blended Order Independent Transparency implementation introduces visual artifacts when multiple translucent surfaces are viewed through one another.
The artifacts look like some kind of shader alpha overflow, causing black pixels to form where the combined alpha of seen textures goes above a certain threshold.

To Reproduce
Steps to reproduce the behavior:

1. Place a 32x1x1 row of translucent blocks.
   1.1. Note: the blocks cannot be of the same type, because the mesher will otherwise combine the faces producing only a single front and back face. Instead, use an alternating pattern of different translucent blocks.
2. View the row of blocks from either end and pay attention to the "most opaque" pixels that intersect with the most faces.
3. Some pixels overflow (?) and turn completely black.

Expected behavior
There should be no black pixels visible.
The color of the pixels should smoothly fade to the average color of the intersecting faces.

Screenshots

Test setup:

Overflow example:

wboit_overflow.mp4

Runtime info (please complete the following information):

• OS: Win 11, 64bit
• Version: v0.0.1 https://github.com/japsuu/Korpi/tree/5e72087247697f91aaa5de23df7a112b14c68d87

Additional context
BWOIT is known for issues like this, and we might need to switch to something else at some point.
As far as I'm concerned, it's good enough for now. Still would like to get this fixed.