fix: bypass third-party custom-elements-es5-adapter that breaks native class constructors (#1458)#1459
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…1458) Problem ------- Pages that ship custom-elements-es5-adapter.js (notably YouTube) monkey-patch customElements.define(). The adapter wraps every registered constructor, assuming it was transpiled to ES5. When our native ES6 class (VSCControllerElement extends HTMLElement) passes through the wrapper, the wrapper tries to call the constructor without `new`, producing: "Class constructor _VSCControllerElement cannot be invoked without 'new'" The previous mitigation (f5c463d) captured the native define() reference in constants.js before the adapter could patch it. This fails because inject.js loads via an async <script src> tag — the page's adapter can execute first, so the "saved" reference is already the patched version. Root cause ---------- There is no way to guarantee our inject.js runs before arbitrary page scripts when using the <script src="chrome-extension://..."> injection pattern. The load order depends on network timing and browser scheduling, making this a non-deterministic race condition. Solution -------- Stop calling customElements.define() entirely. The <vsc-controller> tag name requires no registration to function correctly: - document.createElement('vsc-controller') returns a valid HTMLElement for any hyphenated name, registered or not - CSS tag selectors (vsc-controller { ... }) match by tag name, not registration status - querySelector('vsc-controller') is a pure DOM query, unaffected - element.attachShadow() works on any valid custom element name - element.tagName === 'VSC-CONTROLLER' is set at creation time The removed VSCControllerElement class had no functional lifecycle logic — connectedCallback and disconnectedCallback only emitted debug log messages. This eliminates the entire class of es5-adapter conflicts because the adapter's monkey-patch of customElements.define() is never invoked.
igrigorik
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Capture the native customElements.define() early in the bundle before
any third-party ES5 adapter can monkey-patch it. Use the saved reference
when registering the vsc-controller custom element, preventing the
"Class constructor _VSCControllerElement cannot be invoked without 'new'"
error caused by the adapter's incompatible wrapper around native ES6 classes.