U+2800 BRAILLE PATTERN BLANK is missing from Sans and Serif, causing a glyph to be substituted from another font.
Created attachment 11079 [details] Screenshot from gucharmap
Hi, the glyph isn't missing in the fonts. It's fontconfig which substitutes the glyph because for some reason (probably because it is an empty glyph). I'll forward this to them. Thanks for the report.
Added U+2800 to list of allowed blank glyphs
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