Why does this JavaScript innerHTML XSS?
Why does this JavaScript innerHTML XSS from user content. The JavaScript code assigns user input to innerHTML. In JavaScript this executes any script in the string.
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What's wrong with this JavaScript error in for await?
What's wrong with this JavaScript error in for await not propagating. The JavaScript code iterates an async iterable with for await. In JavaScript errors can leave the loop without handling.
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What's wrong with this JavaScript JSON parse?
What's wrong with this JavaScript JSON parse in an API handler. The JavaScript code checks a parsed object with a truthy test and rejects valid empty payloads. In JavaScript services this drops legitimate requests.
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Why does this JavaScript scheduler drift?
Why does this JavaScript scheduler drift in reporting. The JavaScript code mutates a Date object and reuses it, so every window shifts forward. In JavaScript jobs this breaks hourly aggregation.
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Why does this JavaScript lock file race?
Why does this JavaScript lock file race under concurrency. The JavaScript code checks for a lock file and then creates it, which is a classic TOCTOU race. In JavaScript workers this lets two processes run the same job.
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What's wrong with this JavaScript JSON parse reviver?
What's wrong with this JavaScript JSON parse reviver receiving wrong keys. The JavaScript code uses a reviver to transform dates. In JavaScript the reviver is called with empty string for the root object.
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Why does this JavaScript config leak across tenants?
Why does this JavaScript config leak across tenants. The JavaScript code uses a shallow copy of a nested object, so tenants share nested state. In JavaScript SaaS this silently corrupts settings.
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What's wrong with this JavaScript webhook signature check?
What's wrong with this JavaScript webhook signature check. The JavaScript code uses == on HMACs and a naive timing comparison. In JavaScript integrations this can leak timing information and allow guessing.
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Why does this JavaScript token become predictable?
Why does this JavaScript token become predictable in production. The JavaScript code uses Math.random for session tokens, which is not cryptographically secure. In JavaScript auth systems this enables session hijacking.
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Why does this JavaScript SSL setting break security?
Why does this JavaScript SSL setting break security in a payment client. The JavaScript code disables certificate verification, which makes HTTPS vulnerable to MITM. In JavaScript services this exposes credentials.
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Why does this JavaScript Promise.all lose writes?
Why does this JavaScript Promise.all lose writes in a fan out job. The JavaScript code allows one rejection to cancel all other promises. In JavaScript pipelines this causes partial writes and missing data.
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Why does this JavaScript loop corrupt records?
Why does this JavaScript loop corrupt records in a batch job. The JavaScript code reuses a mutable object across iterations, so every row points to the same reference. In JavaScript pipelines this creates duplicate data.
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What's wrong with this JavaScript cache key?
What's wrong with this JavaScript cache key in production. The JavaScript code forgets to include locale in the key, so users see cached content in the wrong language. In JavaScript apps this causes localization incidents.
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What's wrong with this JavaScript order by?
What's wrong with this JavaScript order by in a search endpoint. The JavaScript code interpolates a user supplied sort field into SQL, allowing injection. In JavaScript backends this exposes data and crashes queries.
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Why does this JavaScript dedupe reorder results?
Why does this JavaScript dedupe reorder results in production. The JavaScript code uses a Set for dedupe but loses original order used for pagination. In JavaScript APIs this causes missing and duplicated items.
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What's wrong with this JavaScript retry backoff?
What's wrong with this JavaScript retry backoff during outages. The JavaScript code retries on a fixed schedule without jitter, so all workers stampede at once. In JavaScript services this keeps the outage alive.
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What's wrong with this JavaScript cache check?
What's wrong with this JavaScript cache check in a quota service. The JavaScript code treats zero as false and refetches on every call. In JavaScript APIs this causes unnecessary database load and latency.
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Why does this JavaScript cache stampede?
Why does this JavaScript cache stampede under load. The JavaScript code recomputes values on expiry without a lock, so every request hits the database. In JavaScript services this melts the backend.
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What's wrong with this JavaScript file save?
What's wrong with this JavaScript file save in a cache writer. The JavaScript code overwrites the file in place, so readers can observe partial JSON. In JavaScript services this causes corrupted reads and crashes.
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1️⃣1️⃣ JavaScript is Faster than Rust? — Chris Heathwood
⚙️ V8 optimizations that make JS outperform Rust (sometimes).
📺 Watch: https://youtube.com/watch?v=FgmRLKAcHOA
#JavaScriptPerformance #V8Engine #RustLang #WebDev #Optimization #JITCompiler #ProgrammingLanguages #FrontendPerformance
