**Do you want to request a *feature* or report a *bug*?**
*Feature*

**What is the current behavior?**
In Firefox the `dialog` element is not implemented. We use a polyfill to be able to support it. Everything works well. But React warns that the `dialog` element is unrecognized, and this on each page load, which is quite useless (for this specific case).
I would like the possibility to disable the  warning but only for some elements. So the utility of this warning remains when the developer mistype the component name.

**What is the expected behavior?**
Once we specified which tag are "accepted/normal" React will not warn on specified unrecognized tags.

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**
React 16
Firefox 57

In previous versions there was no warning.

Is this clear enough? Do you need any other information?
Cheers
updatePayload = [];
        }
      } else {
        
        
        (updatePayload = updatePayload || []).push(propKey, null);
      }
    }
    for (propKey in nextProps) {
      var nextProp = nextProps[propKey];
      var lastProp = lastProps != null ? lastProps[propKey] : undefined;
      if (
        !nextProps.hasOwnProperty(propKey) ||
        nextProp === lastProp ||
        (nextProp == null && lastProp == null)
      ) {
        continue;
      }
      if (propKey === STYLE) {
        if (__DEV__) {
          if (nextProp) {
            
            
            Object.freeze(nextProp);
          }
        }
        if (lastProp) {