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FAQ • Support

When a Base64-Encoded Script Breaks Silently and Nothing on the Page Works

Field Note #162
🔬 Resolved 🟡 Intermediate ⏱ 30 Minutes ✓ Observation from Experience

⚡ Quick Fix (TL;DR)

The Fix: The fix was to identify and remove the stray duplicated code fragment, re-balance the braces, then re-encode the corrected script back to base64 and swap it into the page.

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The symptom
An FAQ accordion on a showcase page would not open when clicked. There was no visible error on the page itself — the elements were present, the classes looked correct, and nothing appeared broken in the markup.
 
Initial assumption
The first instinct was that the click handler wasn’t attached to the right element, or that the FAQ markup itself was structured incorrectly.
That assumption was wrong. The markup was fine.
 
Investigation
 
The page’s interactive behavior (FAQ toggle, category filters, a “View All” button) was all defined inside a single `eval(atob(“…”))` block — the standard pattern used to survive `wptexturize` mangling in WordPress Custom HTML blocks.
Decoding the base64 string revealed a stray, duplicated fragment of code inside one function — an extra closing `});` followed by leftover lines that didn’t belong, almost certainly left over from a prior edit that was never cleaned up.
Because all of the page’s interactivity lived inside one script tag, a single syntax error anywhere in that block caused the entire script to fail to parse. Not just the FAQ — the filter buttons and “View All” button silently stopped working too, even though nobody had reported those specific symptoms yet.
 
What to check
When an interactive element embedded via a base64-encoded script isn’t responding:
1. Decode the `atob(…)` string directly (base64 decode) rather than assuming the visible markup is the problem.
2. Check brace and parenthesis balance in the decoded script.
3. Remember that one syntax error anywhere in the block breaks everything in that block, not just the feature that was reported broken. Check every interactive element on the page, not just the one that prompted the investigation.
 
Current finding
The fix was to identify and remove the stray duplicated code fragment, re-balance the braces, then re-encode the corrected script back to base64 and swap it into the page.
 
Troubleshooting lesson
When JavaScript is delivered as an encoded blob for platform-compatibility reasons, a broken feature is a strong signal to check the *entire* script for a parse error, not just the specific feature that visibly failed. One typo anywhere in the block can silently disable everything else sharing that script tag.

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