entity_translation_overview operations links (add / edit) completely missing in UI

Problem/Motivation

The "Operations" column on the translation overview page of a view is completely empty while the $rows variable in contains the correct link (which is working and accessible if opened manually)!
See function entity_translation_overview($entity_type, $entity, $callback = NULL) in entity_translation.admin.inc, line 310.

The screenshot attached shows the dsm() output of the $rows variable and the output.

The curious thing is, that I am shure it worked some days ago and I have no clue what I did that lead to this curiousity. I'm using the latest .dev version (7.x-1.0-beta3+15-dev).

Proposed resolution

I have no clue to be honest

Remaining tasks

Finding out a reason or when this happened.

User interface changes

None.

API changes

None.