All named HTML entities are specified in chapter 24 of the HTML standard. The only thing missing from the page are rendered entities, but you can easily create your own copy with the additional information by applying a simple regexp:
s/<!ENTITY (S+)/<!ENTITY 1 &1;/
Not all entities are named. For many, you need to specify the Unicode code page, either in decimal (▲ ▲, ▼ ▼) or hex (▲ ▲, ▼ ▼).
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