“veryverythinmathspace”, “verythinmathspace”, “thinmathspace”, “mediummathspace”, “thickmathspace”, “verythickmathspace” and “veryverythickmathspace” are deprecated values for MathML lengths and will be removed at a future date.
MathML 长度的“verythethinmathspace”、“verythinmathspace”、“thinmathspace”、“mediummathspace”、“thickmathspace”、“verythickmathspace”和“veryverythickmathspace”值已弃用，未来将被移除。