fix: chapter preview fine tuning

[luwes]

https://media-chrome-git-fork-luwes-chapter-preview-fix-mux.vercel.app/examples/vanilla/advanced.html

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Name	Status	Preview	Comments	Updated (UTC)
media-chrome	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Mar 6, 2024 4:14pm
media-chrome-demo-nextjs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Mar 6, 2024 4:14pm
media-chrome-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Mar 6, 2024 4:14pm

[codecov]

Codecov Report

Attention: Patch coverage is 70.83333% with 7 lines in your changes are missing coverage. Please review.

Project coverage is 72.36%. Comparing base (3ea80df) to head (c7696c1).
Report is 20 commits behind head on main.

❗ Current head c7696c1 differs from pull request most recent head 0735bd7. Consider uploading reports for the commit 0735bd7 to get more accurate results

Files	Patch %	Lines
src/js/media-preview-chapter-display.js	0.00%	5 Missing ⚠️
src/js/media-store/request-map.js	71.42%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #840      +/-   ##
==========================================
- Coverage   78.55%   72.36%   -6.20%     
==========================================
  Files          59       79      +20     
  Lines       11080    15417    +4337     
==========================================
+ Hits         8704    11156    +2452     
- Misses       2376     4261    +1885     

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[cjpillsbury]

pre-approving with one nitpick blocker (added a suggestion in case you wanna just commit it and merge)