This property defines the Unicodes which belongs to Glagolitic Supplement block
Characters like 𞀀,𞀁,𞀂, etc. are listed under Glagolitic Supplement Block.
43 Characters are present in Glagolitic Supplement Block starting with the Unicode point U+1E000 that represents the character 𞀀.
Currently, as per latest version 15.0.0, Unicode supports 328 number of Block. Here are a few examples - Latin Extended E,Adlam,Aegean Numbers, etc.