1452039 - HTML <object> fallback content issue when attribute type is defined but not data

Status: UNCONFIRMED

(Core :: Layout, defect, P3)

Description

[Gabriele Gervasi]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:61.0) Gecko/20100101 Firefox/61.0
Build ID: 20180405220026

Steps to reproduce:

I can reproduce by following these steps:

<object type="image/png">
  <div style="background:green; width: 200px; height: 200px;">SHOULD NOT BE RENDERED BECAUSE PNG SUPPORTED</div>
</object>
<object type="THISTYPEDOESNOTEXIST">
  <div style="background:red; width: 200px; height: 200px;">MUST BE RENDERED</div>
</object>



Actual results:

The first <object> tag show fallback content for a supported mime/plugin (in this case image/png)


Expected results:

If data is not defined, according to https://dev.w3.org/html5/spec-preview/the-object-element.html main point 5 (If there is a type attribute present on the object element, and that attribute's value is not a type that the user agent supports, but it is a type that a plugin supports, then let the resource type be the type specified in that type attribute, and jump to the step below labeled handler.), probably, the first <object> tag should not render fallback content