Grouped Specifications shows "AllSpecifications" Pseudo group

[kaibrockelt]

Hi!
When displaying the grouped specifications, the code iterates through all groups to render them.
On the product context however, there is one Pseudo-Group "allSpecifications" that - as the name says - contains all specifications in a flat structure.

This has the consequence, that the Specs are shown twice. once in their correspoding group and once below in "allSpecifications".

a PR with the bugfix is on its way.

[kaibrockelt]

Cant tick the boxes on patch and docs. but the PR is open.
#38