Commit #9647 has changed the behaviour of renderAd preventing the ANOutstreamVideo.js renderer from displaying a video ad.

[dbirkbeck]

Type of issue

Bug

Description

The ANOutstreamVideo.js renderer requires access to the top level web page to properly render ads. (It creates it's own iframe as needed.)

Commit #9647 (prebid release 8.25.0) changed the behaviour of the renderAd function disallowing writing to the main document. This breaks the ANOutstreamVideo.js renderer.

It is obvious that no one tested this change against prebid's own example web pages located at:
https://docs.prebid.org/examples/video/outstream/pb-ve-outstream-no-server.html

Steps to reproduce

Enter the current Prebid outstream reference (no ad server) URL in a web browser and append the prebid debug query string as follows:
https://docs.prebid.org/examples/video/outstream/pb-ve-outstream-no-server.html?pbjs_debug=true

Watch for a message similar to the following in the web browser console:
ERROR: Error rendering ad (id: <>): renderAd was prevented from writing to the main document.

Test page

https://docs.prebid.org/examples/video/outstream/pb-ve-outstream-no-server.html?pbjs_debug=true

Expected results

The ANOustreamVideo.js renderer should be allowed to display a collapsable video ad.

Actual results

The following error message is logged to console instead of a video ad being rendered:
ERROR: Error rendering ad (id: <>): renderAd was prevented from writing to the main document.

Platform details

All releases of Prebid after and including 8.25.0
All platforms

Other information

[patmmccann]

interestingly #10944 also flagged but we missed the relationship