I think I’ll have to agree with Thomas here. Using accordion tabs plugin also and 5.6.6 crashed my site with fatal error due to a naming collision. Cost me about 7 hours today to figure it out as I was updating many plugins at once and had to determine which one. Only option is to roll back to the previous version. Please fix the naming collision and test with all related plugins in the future. Absolutely killer plugin, but this was a basic mistake it seems.
