webcomponents / webcomponents/polyfills
[Custom Elements] Calling `setAttribute` with a non-lower cased attribute name does not trigger `attributeChangedCallback`
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Severity: Medium
Type: Bug
wontfix
- Dominant language
- HTML
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Description
If `foo` is in `observedAttributes` and `setAttribute('FoO', '2')` is called, in Chrome with native custom elements, the `attributeChangedCallback` is called with the attribute name set to `foo` (lowercased). When using the custom elements polyfill, the `attributeChangedCallback` is not called..
See: http://jsbin.com/fiyufid/edit?html,console,output
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