Single underscore symbol (weight is inconsistent / mispositioned) with the double underscore ligature on different font size and font face

Extends the issue #1361.

The referred issue seems to be an isolated case from a certain terminal app, however, it does not. The following figures show that a certain font size shows that the weight (thickness) is inconsistent or mispositioned / misaligned between the single underscore and the double underscore ligature,

Font Section Test in Windows GIF

This section shows the inconsistencies from a variety of font faces at a certain font size. Note that the first picture (top) has a spacing of Normal while the second one (bottom) has a spacing of Terminal. I just wanted to see if they have different results.

font_test_normal font_test_term

Upon checking, the issue starts at 8 to 19 points. 20 points beyond does not show any issues.

Terminal Test

This section shows how it appears in terminal + demonstration.

on_terminal WindowsTerminal_A34e3BVwKb

This second picture was taken from my nvim.

Other Application: Notepad

This section clears the assumption that the terminal may be the one at fault for misrendering the symbol, however, this also affects Notepad and other applications. Though, in applications like these, it was quite unnoticed until at a certain font size.

on_notepad

Closer Inspection

This section shows the inconsistency when zoomed in. This does not adjust the font size over time.

closer_inspection

Upon checking #1360, this may be an offset issue than a weight inconsistency issue, though, in my GIF sample, it feels like a weight issue.

What I have tried:

Tried to explicitly state that the underscore must be on low, high and above-baseline and the bug still appears.

Additional notes:

The font was built with the iosevka-docker given from the building from source section.
The font I have is built as a SuperTTC, though I think this does not affect the output.
The font was not patched with Nerd Font and Powerline Ligatures.

Your font version: (Release or git, version): Fetched via Git, 15.6.1
Your font variant: Pragmata Pro Style (SS08), Discretionary Ligatures (dlig), Sans Serif, and Standard (Normal + Extended)
Your operating system (name and version): Windows 11, Version 21H2
Your application using Iosevka: Terminal (Windows Terminal with pwsh (Powershell), and Essential Apps (ie. Notepad).
Private Build Plans (if needed): https://github.com/CodexLink/dotfiles-configs-archive/blob/latest/font-recipe/private-build-plans.toml

I retried everything from scratch and it seems that I could get it right with underscore set to high. I just noticed that whenever you override one of the design variants of a specific character, there will be an indent after the variant. I noticed this and it seems that the options that I did for the underscore now work. I apologize for this issue being too informative but missed that small detail that could have avoided this lengthy issue.

Though it should be noted to the user who wants to create through the font through the customizer that at some point, once the variant is applied, there might be potential inconsistencies from the character with the ligature that it may associate with them, such as the one provided here (the underscore stacking with the connected underscore ligature).

I reopened it for others to see, or for you to see (to acknowledge it), though the issue is already fixed.

be5invis / Iosevka