I am trying to create a Civi rule that will be triggered by "Membership is changed" and then set the end date of this membership to a new value. (This rule is needed as a workaround for another bug in how CiviSepa interacts with one-time membership contributions.)
When I create an Action for this rule, I select "Update Date Value", as this seems to be the action most close to what I need (modify end date). I get redirected to a page asking for "Source Field", "Target Field", "Operation" and "Operand". When I click on the down-arrow on the right side of "Source Field" and "Target Field", no drop-down menue is opening. Instead, only a grey line appears when I click, and disappears when I click again. The same happens when I select the action "Advanced Update Date Value".
Does anybody know what could be the problem here? I get no error whatsoever. The rule has no Conditions and no Delay-Action, it contains nothing but a name and a trigger.
Edit: I tested this on a CiviCRM demo page running the version 5.62.0. In this demo system, I was able to add a Rule with the trigger "Membership is changed" and the action "Update Date Value". I was able to choose "Start Date" in "Source Field" and "End Date" in "Target Field".