Jason

I rolled back to an earlier version (5.6.6) and it started working again, but it’s not working in later versions nor the current version.

(The user, dodgethat, mentioned that this was also the case in their support request for JavaScript not loading in their Custom Product Tabs.)

I am having the same issue on all of my websites since the 3.0.6 update.

I am having this same issue on all of my websites. It appears to be an issue introduced in version 3.0.6.