Bug 25297 – <object type="text/html"> shows scrollbars even when overflow : hidden is specified

• Status: NEW
• Component: Scrolling

[C Snover]

Since <object type="text/html"> is the XHTML Strict DTD replacement for <iframe>, it would be good if a mechanism similar to iframe’s scrolling="no" property was provided, since the embedded page can not always be changed to include “html,body{overflow:hidden;}” (in particular, pages from 3rd party ad networks).

WebKit should probably do what Gecko does and ensure that scrollbars do not appear when overflow : hidden is specified on the <object>. (I am pretty sure this is the correct behaviour under CSS 2.1, but I am not an expert at reading the CSS spec. :))

Alternatively, a <param> could be used that is directly analogous to the <iframe> attribute (eg. <param name="scrolling" value="no" />).

Either way, currently, WebKit does not offer feature parity in this area for the old <iframe> functionality, and this causes layout ugliness on XHTML 1.0 Strict pages.

See URL for testcase.

[C Snover]

WebKit conforms to CSS 2.1 specification in this regard — it was changed between CSS2 and CSS2.1. See CSS 2.1 § C.2.79.

However, before closing this bug as INVALID, this is still a minor regression in functionality that ought to be resolved somehow, especially since HTML5 (as currently proposed) removes the "scrolling" attribute from <iframe>, too.

[Ahmad Saleem]

I am changing the status of this bug to "New" because in all other browsers (Firefox Nightly 106 and Chrome Canary 107) on test case from URL, I get three <div> but in Safari 15.6.1 and Safari Technical Preview 152, I only get plain page and <div>s are missing. I think we regressed in behaviour and scrollbar is not just an issue now.

I tried this in "Private Mode" as well to confirm, it is not cache issue and disabled any extension as well.

Tagging Webkit engineers for their input. Thanks!

[Ahmad Saleem]

(In reply to Ahmad Saleem from comment #2)
> I am changing the status of this bug to "New" because in all other browsers
> (Firefox Nightly 106 and Chrome Canary 107) on test case from URL, I get
> three <div> but in Safari 15.6.1 and Safari Technical Preview 152, I only
> get plain page and <div>s are missing. I think we regressed in behaviour and
> scrollbar is not just an issue now.
> 
> I tried this in "Private Mode" as well to confirm, it is not cache issue and
> disabled any extension as well.
> 
> Tagging Webkit engineers for their input. Thanks!

From Plain page, I get following (also highlighting where <div>s are missing).

<object> of type text/html with overflow : hidden

[[[ MISSING DIVS ]]]]

References: CSS 2.1 § 3.1, CSS 2 § 11.1.1, CSS 2.1 § 11.1.1, CSS 2.1 § C.2.79

Bug reports: WebKit Bug#25297, Opera Bug#DSK-251530