Facebook Test Event Tool Buggy?


wonder if anyone is experiencing (or has experienced) the same.

I have set up many server-side setups with GTM for clients and the FB Test Event Tool always showd proper deduplication with the browser event being processed and the server event deduplicated.

However, recently (since about a month), I frequently don’t receive the browser event in the Test Tool and if it shows both events show as deduplicated. The server event always comes in.

I think the browser event fires properly as it shows in Pixel Helper and also the network request has a 200 status code. But it only shows up in the Test Event Tool when I have openend the Developer Tools for both the Test Event Tool tab and the website tab where the events are being fired. But even then, the browser events don’t show reliably.

This also happens for pixels/setups that showed up all fine before (didn’t change the setup).

Now in the overview tab the deduplication stats look good, so it is working, just the Test Event tools shows rubish.

Generally, I wouldn’t mind so much, but clients are frequently hesitant to believe that everything is working if the test event tool doesn’t show the expected views for deduplication.

I can’t for the life of me figure out what is going on. I reset browser cache, deleted cookies, even switched browser, but it is always the same. Also no ad or script blockers installed.

Any tips would be highly appreciated.
Thank you!

1 Like


I periodically encounter the same problems in FB test tool as well. Very often only server events with deduplication mark are shown.

I also tried to solve it by clearing cookies, changing browser, etc. - all to no avail.

In once instance Test Tool refused to load at all (for a particular Pixel), astonishingly, I resolved this by changing account language.

In another case, customer has two Pixels - one displays everything correctly, the other only shows server-deduplicated.

I believe there is no tried and proofed solution for this. Loks like young and small startup such as Facebook just isn’t capable of designing a properly working tool. Perhaps in year or so… :slight_smile:

Hi Guys,

Test Tool is buggy, that is to say the least. I face the same thing like… every other day, however gazillion page refreshes seems to help sometimes.

If one container is set to send events to two Pixels, I always get the situation that Alex describes - first one shows everything correctly, other one shows either only server or only browser with deduplication label.

I totally agree with @sashage it’s a pain to explain this to customers, since such reasoning always sounds like some urban voodoo, however this is the reality of FB. One other “great” thing you guys may have noticed is your test events are actually aggregated to Overview tab (and mess up the stats).

What I do sometimes when customers refuse to believe this, is I set up either Telegram or Slack tags for same triggers that my FB events have - those send simple text notifications which shows tags fire correctly (you can include event_id for even more proof).

Overall, test tool is rather unreliable and I treat GTM debug as model, always.

Thanks @Alex @Dan!

Glad to hear that it is not just me. This issue is driving me nuts :slight_smile:
Hope Facebook gets it fixed soon.