Q: Why browsingTopics: true by default on all outgoing bidder requests?

[orazumov-zeta]

Type of issue

Question

Description

Why browsingTopics: true by default on outgoing bidder requests? (sources)
Related PR: Core: enable Sec-Browsing-Topics header on outgoing bidder requests #10340

Not all bidders support this. As a result, in Chrome console, I see numerous errors of the type 'Attestation check for Topics on URL failed.' There is an option 'topicsHeader' to control this. Perhaps it would be better to have browsingTopics enabled not by default, but only when this option is explicitly specified?

Steps to reproduce

Open the Chrome browser console on any page where Prebid.js is running with configured bidders that do not support browsingTopics (for example, appnexus, mediafuse, sovrn, minutemedia, etc.). You will see errors Attestation check for Topics on URL failed.

Test page

Here you can see such error: https://www.bmwblog.com/2024/02/26/how-a-bmw-7-series-turned-from-city-cruiser-to-off-road-adventurer/

Expected results

Actual results

Platform details

Prebid.js 8.35
Chrome 121.0.6167.184 (Official Build) (arm64)

Other information

Core: enable Sec-Browsing-Topics header on outgoing bidder requests

[dgirardi]

Are those error messages a problem? As far as I know they are inconsequential, so it seems reasonable to try to include topics by default, since for the exchanges that can accept them they are valuable.

[patmmccann]

We were hoping the error messages would encourage adoption. The Chrome team actually noted this in their repo patcg-individual-drafts/topics#289

My inclination is bidders generating warnings should handle individually.

[dgirardi]

We can set suppressTopicsEnrollmentWarning: true unless debug is true.

[msperone]

A fix for this error would be greatly appreciated! I understand the perspective of throwing errors to encourage adoption of the feature. But this is a lot of noise in the javascript console and has caused my team to miss some legitimate errors.

I like the idea to suppress the error unless debugging is turned on.