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Predictive prefetch makes duplicate HTTP requests still causing duplicate ad impressions

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  • Last reply by Shadow110

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Hey guys,

I look after implementation of tracking on our website and our QA team raised an issue that there are duplicate tracking GET calls/ad impressions. I went to DB to confirm this and indeed noticed duplicate tracking GET calls/ad impressions.

Scenario is : click on product tile on one of our pages and look at network calls, there should be only one impression tracking call onclick. But there are two.

I found this issue that was raised for Firefox 52, I use Firefox 57.0.1 on MacOs Sierra and still get this issue. https://www.fxsitecompat.com/en-CA/docs/2017/predictive-prefetch-makes-duplicate-http-requests-in-iframes-causing-false-ad-impressions/

Steps to reproduce:

1. Go to https://www.appliancesonline.com.au/indesit-xwa71283waus-7kg-front-load-washing-machine/ 2. Scroll to the bottom of the page, You may also like section 3. Open network tab, check persist logs, filter by sp. (snowplow tracking calls) 4.Click on any product in you may also like section. 5. Observe snowplow network calls, there will be impression click duplicates. Screenshot attached. First and third call are duplicates. Call starts before page load and duplicates itself when new page is loaded.

I believe this behaviour is because of predictive prefetch? Your help would be appreciated

Hey guys, I look after implementation of tracking on our website and our QA team raised an issue that there are duplicate tracking GET calls/ad impressions. I went to DB to confirm this and indeed noticed duplicate tracking GET calls/ad impressions. Scenario is : click on product tile on one of our pages and look at network calls, there should be only one impression tracking call onclick. But there are two. I found this issue that was raised for Firefox 52, I use Firefox 57.0.1 on MacOs Sierra and still get this issue. https://www.fxsitecompat.com/en-CA/docs/2017/predictive-prefetch-makes-duplicate-http-requests-in-iframes-causing-false-ad-impressions/ Steps to reproduce: 1. Go to https://www.appliancesonline.com.au/indesit-xwa71283waus-7kg-front-load-washing-machine/ 2. Scroll to the bottom of the page, You may also like section 3. Open network tab, check persist logs, filter by sp. (snowplow tracking calls) 4.Click on any product in you may also like section. 5. Observe snowplow network calls, there will be impression click duplicates. Screenshot attached. First and third call are duplicates. Call starts before page load and duplicates itself when new page is loaded. I believe this behaviour is because of predictive prefetch? Your help would be appreciated
Attached screenshots

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Seems this is going no where fast.

If you have a bug, file a bug report. https://bugzilla.mozilla.org/ Bug Writing Guidelines : https://developer.mozilla.org/en-US/docs/Mozilla/QA/Bug_writing_guidelines


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