Fix HTML DOCTYPE escaping issue in rendered output#25
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Co-authored-by: mahata <23497+mahata@users.noreply.github.com>
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[WIP] HTML markup issue: DOCTYPE and <head> contents are incorrect in rendered output
Fix HTML DOCTYPE escaping issue in rendered output
Jul 9, 2025
mahata
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Jul 9, 2025
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The browser was receiving invalid HTML markup where the DOCTYPE declaration was being HTML-escaped and placed inside the document content instead of at the very beginning as required for valid HTML5 structure.
Problem
Before: The DOCTYPE was rendered as escaped text inside the HTML content:
After: The DOCTYPE is now properly placed unescaped at the document start:
Root Cause
The issue was in
hono/routes/index.tsxwhere the DOCTYPE was being rendered as a JSX text node inside a fragment:JSX fragments treat string literals as text nodes that get HTML-escaped for security, which caused the DOCTYPE to be rendered as
<!DOCTYPE html>instead of the required unescaped<!DOCTYPE html>.Solution
Changed to use template literal concatenation to ensure the DOCTYPE appears unescaped:
Validation
The application continues to work exactly as before, but now with proper HTML5 document structure that browsers can parse correctly.
Fixes #24.
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