# Cypress v0.20.0 — Release & Upgrade Intelligence
- **Product:** Cypress (https://www.cypress.io)
- **Version:** v0.20.0
- **Released:** Jul 19, 2018
- **Impact Score:** 7/10
- **Breaking Changes:** Source flagged
- **Canonical Analysis:** https://changelogs.us/cypress/updates/v0.20.0/

## Executive Summary (TL;DR)
Cypress v0.20.0. Source highlight: *Released 09/10/2017*

## Breaking Changes & Deprecations
- - `0.20.0` is our biggest technical release ever. It accounts for more than 2,000 commits. It's full of breaking changes we wanted to land prior to having our public `1.0.0` release.
- Breaking Changes:** - We've removed the undocumented `cy.chain()` command. You should be able to safely remove this from your code. Fixes [#456](https://github.com/cypress-io/cypress/issues/456).

## Improvements
- Using mocha's `done` callback now works correctly. We've improved mocha's handling of uncaught exceptions and properly associate them to test failures. <OPEN AN ISSUE>
- Improved command subject validation error messages.
- Improved the element detachment error messages (when you try to interact with an element that's become stale / detached from the document).

## Bug Fixes
- Whenever you encounter errors in the CLI we'll output helpful debugging information at the bottom of each error.
- You can use the new environment variable `DEBUG=cypress:cli` to see debugging output from the CLI.
- We've removed the undocumented `cy.chain()` command. You should be able to safely remove this from your code. Fixes #456.
- Updated `Cypress._` to use lodash instead of Underscore. Fixes #548.
- If any of an element's parent's overflow is 'hidden', we now calculate if the element is outside of the boundaries of that parent element and validate visibility assertions accordingly. This may cause some tests that were previously passing to now accurately fail. Fixes #410.
- .select() should now look for the trimmed value inside of an `<option></option>`. This may change the content argument required to select the option you intended in your .select() command. Fixes #175.