Class X becoming X__wab_instance in implementation.

I am adding a class X to a component, but in implementation, it becomes X__wab or X__wab_instance … What is going on?
Image 1: Div with the X__wab_instance… I would have expected just X (X = sb-collection-header-simple-list), or at least X and X__wab__instance…
Project: k5wi36LTCNmnJb5rh2sgis

(Coming back with comopnent / page info in a bit… Plasmic is having issues loading)

Not sure if it happens always, but it definitely happens when I do SSR…
Need to find the elements in js using this:

document.querySelector('.sb-collection-header-simple-list, .sb-collection-header-simple-list__wab_instance')

Page with issues:
Project: k5wi36LTCNmnJb5rh2sgis
Name: PCP: Tea Gift Shop [Header]