Chrome 54 - Intervening against document.write()

[timh4288787]

Hi

I use DTM's "JavaScript / Third Party Tags" scripts (Sequential and Non-Sequential HTML varieties) to trigger marketing tags on website pages (think Google conversions or Doubleclick Floodlight).  Recently, a message started showing up in Chrome's console.

(Click to enlarge example of console warning message.)

I found that Google will begin blocking document.write() of 3rd-party scripts on slow (2G) connections starting in mid-October.  https://developers.google.com/web/updates/2016/08/removing-document-write?hl=en.  I therefore expect my 3rd-party tags to not work via DTM starting in mid-October. It's unfortunate because it's a useful feature to us.

1. Is there awareness in the community of this change? 
2. Does anyone read this differently?
3. Does anyone know if Adobe is something to address it?  I have a question in to ClientCare but haven't heard back yet.  Perhaps the community could also help.

Thanks for any input. 

[taciac]

Hi Tim,

Thanks for reaching out. We have a ticket in to Engineering about this. I should have some more information soon.

-Tacia

[andrew_r-GrfLbX]

Thanks, keen to find out information on this as well as our technology teams are keen to move away from utilising document.write across our digital estate.

[corey_spencer · Accepted solution]

Due to the limited usage of 2G network, we expect the current 2G Google intervention to a minimal impact on enterprise customers at this time. We are proactively addressing future issues that may develop if Google continues to promote practices that contradict Internet community standards.

DTM’s goal has always been to create and support the most powerful and flexible features in the space. We believe that must include allowing our users to leverage both synchronous and asynchronous technologies.

Customers who are significantly concerned about 2G Chrome users can use a more asynchronous deployment of DTM and continue to use the robust set of asynchronous specific features of DTM.

If you are seeing this warning and want to use DTM with a more asynchronous deployment, and remove all “document.write” calls (and remove the warning), please do the following.

3rd Party Tag

If you are deploying 3rd party tags or JavaScript via rules in DTM, and are concerned about visitors on a 2G cellular network who are using Chrome, please do the following:

1. Review all 3rd scripts that are deployed via “Sequential Javascript” or “Sequential HTML” for “top of page” or “bottom of page” positioning rules.
2. In the code editor, change the Type to “Non-Sequential Javascript” or “Non-Sequential HTML”. Note: any functionality that requires synchronicity will no longer work. 
3. Review the code within the editors to ensure it isn’t using “document.write". If the code you are deploying through DTM uses “document.write” it may be affected. 
4. Test well before deploying. 

More information here: https://marketing.adobe.com/resources/help/en_US/dtm/c_chrome_2G.html

[andrew_r-GrfLbX]

what about Adobe's own tools which throw the document.write warning namely mbox.js and target.js. Will these be updated or will users be forced to move on to at.js? If the latter then when will at.js be supported by DTM?

[jantzen_b]

Hi,

Our engineering department is actively working with Google to understand the full impact of the changes. We are also looking into the Adobe libraries that utilize the document.write functionality. As you pointed out, at.js does not use document.write and thus is not impacted. We always suggest our customers update their implementations to the latest code libraries for all solutions. With that being said, we will be updating DTM to support at.js in the near future.

Thanks,
Jantzen