Combinable & Uncombinable cart rules, just plain missing

[heliumdream]

Hello,  recently my client informed me about one of their features acting up with their Prestashop installation. 

They were setting up new cart rules for cyber monday, and wanted to exclude this blanket % discount from being stacked with other offers. Well on the cart rule page, conditions tab, where the checkbox 'Compatibility with other cart rules' drops down, the Combinable & Uncombinable  content areas are blank, failing to show our other cart rules and their interactions with one another. 

I'm unsure when this issue arose, as in the past the client has been able control these without problems.

Any idea?

Edited December 11, 2019 by heliumdream
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[partiid]

Same problem here! Have you resolved it?