The Browser Agent, sometimes called the JS agent, has multiple variants: Lite, Pro, and Pro+SPA. Unless noted otherwise, all features/improvements/bug fixes are available in all variants of the agent.
Do not instrument SPA without a wrappable XHR: In browsers that don't orchestrate the wrapping of XHR, the SPA agent does not collect event data, only metric timeslice data. The agent will still report SPA for browsers that support XHR wrapping. Mobile Safari and a few other browsers didn’t support wrapping the XMLHttpRequest, so they would not produce event data for instrumenting Single Page Apps. They still collect other types of metrics.
Support setTimeout with a string duration: When you call setTimeout with a string as the duration, browsers will cast this as a number, but the agent did not handle this correctly. We are now handling this case correctly.
Work around mutation observer memory leak in IE 11: We have discovered that MutationObserver in IE causes a memory leak, so the agent now will prefer setImmediate for IE, and use a resolved promise to schedule the wrapping in Edge (and other browsers that support promises).
Handle short recursive timers: Some libraries recursively set timers that left our interactions open. The agent now handles this by reducing the max time it will allow to be included in the interaction.
How to upgrade
To upgrade your agent to the latest version, see Upgrade the Browser agent.