Problem

API definitions are taking long time to display in catalog UI. Often times the browser fails or prompts to disable a script that slows down the page.

Resolution

• Login to JAI
• Go to Menus > Main Menu > APIs
• Go to API Catalog tab and set "Swagger UI layout" to single column
• Check whether the issue is still reproducible

After this change the API should load successfully. With the multi-column layout there is a navigation on the left side and all endpoints are expanded by default (that's why parsing is performed for each endpoint which causes the issue in case of bigger API definitions). In a single-column scenario there is no navigation on the left side and all endpoints are collapsed by default.