React: Iframe load event not firing in Chrome and Safari when src is 'about:blank'

[pirelenito]

See: https://jsfiddle.net/pnct6b7r/

It will not trigger the alert in Chrome and Safari, but it will work in Firefox and even IE8.

Is this a React issue or Webkit issue? If it is a Webkit issue, should we "fix it" in React given that we want consistent events across browsers?

ps: The JSFiddle was based on the isuse #5332.

[jimfb]

Unlike in #5332, this does appear to fire in chrome (http://jsfiddle.net/x14c21g0/) so it's odd that we're not firing the event in React.

[suprise]

+1

[vincnetas]

+1

[SmoooZ]

+1

[gaearon]

Please don‘t +1. If you’d like to see this fixed, please help figure out why this happens and/or contribute a fix.

[ndugger]

I am experiencing this issue as well with embed tags when trying to listen to whether or not a PDF has loaded, or has at least started loading.

[aweary]

So the reason that we don't dispatch is because the load event is being dispatched by the browser synchronously when the iframe is appended to it's parent. Since this happens during the commit phase the event is ignored since we disable the synthetic event system while committing.

There's some context on this in https://github.com/whatwg/html/issues/490. There's ambiguity in the spec around load events for iframes and about:blank, which is why we don't see this behavior in every browser.

Outside of waiting for WATWG and browser vendors to resolve this ambiguity, resolving this would probably involve implementing a event queue that enqueues a subset of events during the commit phase and dispatches them afterwards.