Full Page Cache in Magento interfering with results
There seems to be a conflict with using a full page cache on the site and Optimizely. The results page shows the number of times a variation is dsiplayed, however the clicks are not getting registered. The first test I set up is testing a text link for CHECKOUT and a graphic. In Google Analytics, I have had 15 completed transactions but Optimizely is showing only 4 clicks on the checkout button, and we know that not everyone that clicks checkout completes the process so this hsould be much larger than 15.
I created another test on a page that is not cached, using 2 different logos, and the tracking was 100% on it.
This is a Magento store with many plug-ins but the full page cache that is currently installed is Zoom.
Is there a modification that I can make so that I can continue to test without having issues with the full page caching interfering?
As you have discovered, the source of the goal tracking issue lies with the static nature of FPC (full-page caching). Since Optimizely must operate dynamically, your best option is to turn off caching on the URLs where you are running Optimizely experiments.
Secondarily, there is a process known as "hole-punching" with FPCs that can allow for dynamic content. You can find a brief introduction to the topic in this blog post by Thomas Lackemann. I would wager that you could restore tracking on FPC pages if you could load our Optimizely snippet into a dynamic block that is not cached. Hopefully a fellow Magento/Zoom user in the community can confirm.
Let me know what you find!