﻿---
title: Advanced topics
description: How to interpret long task spans in the UI, Using with TypeScript, Initial Page load transaction names, Custom Transactions. 
url: https://docs-v3-preview.elastic.dev/elastic/apm-agent-rum-js/tree/main/reference/advanced-topics
---

# Advanced topics
- [How to interpret long task spans in the UI](https://docs-v3-preview.elastic.dev/elastic/apm-agent-rum-js/tree/main/reference/longtasks)
- [Using with TypeScript](https://docs-v3-preview.elastic.dev/elastic/apm-agent-rum-js/tree/main/reference/typescript)
- [Initial Page load transaction names](https://docs-v3-preview.elastic.dev/elastic/apm-agent-rum-js/tree/main/reference/custom-transaction-name)
- [Custom Transactions](https://docs-v3-preview.elastic.dev/elastic/apm-agent-rum-js/tree/main/reference/custom-transactions)