[USE] Several characters are in two USE classes each

[NorbertLindenberg]

U+00A0 has general category Zs, which puts it into USE class OTHER. It has Indic syllabic category Consonant_Placeholder, which puts it into USE class BASE_OTHER.

It should be BASE_OTHER, as the Unicode Standard recommends this character as the base to show nonspacing combining marks in isolation.

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• ID: 194a6d3c-4137-46e9-3a4b-44b990200986
• Version Independent ID: a0c8e788-5228-aa28-670e-3ba1ac3faecd
• Content: Creating and supporting OpenType fonts for the Universal Shaping Engine - Typography
• Content Source: typographydocs/script-development/use.md
• Product: typography

[Richard57]

Given that Notepad on Windows 10 at least (but not Word of Microsoft Office Standard 2016 on Windows 10) is treating it as BASE_OTHER, I suggest the second line for the O/OTHER derivation be changed from "White space characters, UGC=Zs" to "This includes white space characters, UGC=Zs, except for U+00A0", or simply deleted as redundant. Failing that, mention that U+00A0 is an exception.

[NorbertLindenberg]

Several other characters also are in two USE classes each:

U+0F01: InSC-A=Consonant → BASE; gc=So → SYM
U+0F04..U+0F06: InSC-A=Consonant → BASE; gc=Po → BASE_IND
U+104B: InSC=Consonant_Placeholder → BASE_OTHER; gc=Po → BASE_IND
U+1800, U+1807, U+180A: InSC-A=Consonant → BASE; gc=Po → BASE_IND
U+200D: jt=C → BASE; InSC=Joiner → Zero width joiner
U+11A3F, U+11A45: InSC=Consonant_Placeholder → BASE_OTHER ; gc=Po → BASE_IND
U+1E14F: InSC-A=Consonant → BASE; gc=So → SYM

InSC-A here means Indic_Syllabic_Category Additional.