Creating Custom Filters in Insights Reports Using Regex for Item Attributes

Hey all, I’m trying to replicate a standard filter with a custom event property on an Insights report. The filter is on an attribute (“items”) that is an array of objects. Example: items = [{item_variant: “A”, sku: “1000”}, {item_variant: “B”, sku: “2000”}] In the Insights report, I can easily create a filter (see screenshot below). However, I’m not sure how to create the same filter using a filter with a custom property. The reason why I’d like to use a custom property is to use a regular expression instead of an exact match for the sku attribute. Thanks for your help!