From what I can see the items in the compendiums fail to load when clicked on, because they are attempting to run through the 5e simplifyRollFormula function. This function attempts to validate the roll formula by passing the formula into the Roll function, as there is no monster attached to the items in the compendium it throws a type exception. This is new functionality added with the most recent version of the 5e system see merge requests !432 Release 1.5.0,!428 in the 5e repo.
I solved this locally by editing scripts/classes/GmmItem.js and removing all instances of ,rollData in simplifyRollFormula calls. It was affecting things in a monster too and I couldn't open it any longer.
From what I can see the items in the compendiums fail to load when clicked on, because they are attempting to run through the 5e simplifyRollFormula function. This function attempts to validate the roll formula by passing the formula into the Roll function, as there is no monster attached to the items in the compendium it throws a type exception. This is new functionality added with the most recent version of the 5e system see merge requests !432 Release 1.5.0,!428 in the 5e repo.