[BUG] Social media feature does not work for tiddlywiki with external core

[Leilei332]

Describe the bug

Tiddlywiki with external core don't have social metadata rawmarkup (unless $:/core/templates/social-metadata is edited to transform from a shadow tiddler):

Compared to normal one:

Expected behavior

External core version should have social metadata.

To Reproduce

View the source of https://tiddlywiki.com/prerelease/external-5.3.8-prerelease.html

Screenshots

No response

TiddlyWiki Configuration

v5.3.8-prerelease

Additional context

• social-metadata feature not working in external core sites tiddlyhost/tiddlyhost-com#398
• https://talk.tiddlywiki.org/t/social-metadata-not-working/13023/10