User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Firefox/78.0

Steps to reproduce:

1. Visit https://dopiaza.org/tools/datauri/examples/index.php
2. Drag the image of the cat next to the current tab (as if to open it in a new tab)

Actual results:

Nothing happens.

Expected results:

The image should be opened in a new tab, as it is for regular images (eg. if you drag avatars from Bugzilla).

Got an error from the Browser Console:

NS_ERROR_DOM_BAD_URI: Component returned failure code: 0x805303f4 [nsIScriptSecurityManager.checkLoadURIWithPrincipal] ContentAreaDropListener.jsm:156
    _validateURI resource://gre/modules/ContentAreaDropListener.jsm:156
    dropLinks resource://gre/modules/ContentAreaDropListener.jsm:320
    dropLinks chrome://browser/content/browser.js:3860
    on_drop chrome://browser/content/tabbrowser-tabs.js:725
    handleEvent chrome://browser/content/tabbrowser-tabs.js:1725

This goes back to bug 280056. Not sure if there's a legitimate security concern for data: URLs we'd open a new tab for.

I think we can re-enable dropping data: URLs because they no longer inherit security context (bug 724161). Chrome accepts dropping data: URLs to tabs.

Okay.