Rendering issue with, and questions about, Symbols for Legacy Computing

[EnronEvolved]

First of all, I'd like to add that Ghostty's rendering of semigraphical characters is top-notch, and certainly more comprehensive than Alacritty, but my tests have identified a few likely rendering errors and some potential pitfalls.

• The pitfalls: U+1FBB5 (🮵) to U+1FBB8 (🮸) are specified in terms of one-eighth blocks. How should their rendering be overridden without clobbering the rendering of the arrow, if at all?
• Rendering error: isn't U+1FBAF (🮯) meant to be shorter? It stretches all the way to the top and bottom of the cells for me, and renders identically to U+2542 (╂), even at massive font sizes. This behaviour doesn't seem to be borne out by their distinct renderings elsewhere.
• Possible rendering errors: are the more complicated SLC semigraphics (🯁🯂🯃, 🮲🮳, and 🮹🮺) even in scope for special rendering? I presume they aren't, but I thought it was worth asking as they're not rendering contiguously for me. I'm not sure how to identify the font Ghostty is using for them, but they look block and have gaps at their right-hand edges.

I note (simply for the record) that U+1FB7C (🭼) to U+1FB7F (🭿) are rendering exactly as intended, as they are composed out of two one-eighth blocks rather than being a specific thickness. They may look stretched compared to their reference glyphs, but that is because those glyphs are square, not rectangular.