fix(helper): self-removing bootstrap script avoids React hydration mismatch#121
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…n mismatch The injected bootstrap <script> is prepended right after <!DOCTYPE>, which the HTML5 parser relocates into <head>. Next.js app-router (and any other framework that hydrates from the <html> root) sees an extra child not present in the React tree and reports a hydration mismatch. Fix: have the bootstrap script remove its own <script> tag from the DOM at the end of the IIFE. `document.currentScript` is set during synchronous script execution, so removal runs before hydration. Side effects (console interception, error listeners, and the requestIdleCallback-deferred asset loads for client-log.js and feedback/script.js) survive removal because they're attached to window/console, not the script element.
New clippy lint in latest stable flags `sort_by(|a,b| a.x.cmp(&b.x))` on a Copy key — `sort_by_key(|a| a.x)` is equivalent and idiomatic. Unrelated to the hydration fix but blocks CI.
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Summary
<script>injected byveld_injectlands between<!DOCTYPE>and<html>. HTML5 parser relocates it into<head>. Next.js app-router hydrates from the<html>root and reports a hydration mismatch because the script is not in the React tree.<script>tag viadocument.currentScript.parentNode.removeChild(...)before returning. Runs synchronously during script execution, before React hydration walks the live DOM.window/console; the dynamically-loadedclient-log.jsandfeedback/script.jsare scheduled viarequestIdleCallbackand usedocument.head.appendChild, independent of the bootstrap tag's presence.Why this is safe
document.currentScriptis non-null during synchronous inline script execution.__veld_cldedup guard sits onwindow, not the DOM, so re-injection on the same page is still a no-op.if(s&&s.parentNode).Workaround removed
Previously users had to use
next/scriptwithstrategy="beforeInteractive"to dodge the mismatch. No longer needed.Test plan
cargo test -p veld-helper caddy::tests::test_bootstrap— 13 passed (includes newtest_bootstrap_script_self_removescovering all 3 feature combos)cargo build -p veld-helperclean