Empty boxes

The mistake

The font swapped in for the shop's UI has no glyphs for digits 0–9. When the renderer can't find a glyph in the active font (and no fallback font is configured for that range), it substitutes the standard .notdef box for every character in that range, so every price on the site displays as a row of empty tofu boxes instead of numbers. The font file was only checked for completeness by eye against expected text, not validated against the actual Unicode ranges the site needs (digits, currency symbols, etc.) before being deployed.