Firefox 88 for developers

This article provides information about the changes in Firefox 88 that will affect developers. Firefox 88 was released on April 19, 2021.

Note

See also Never too late for Firefox 88 on Mozilla Hacks.

Changes for web developers

Developer Tools

HTML

No changes.

CSS

Removals

JavaScript

HTTP

Security

No changes.

APIs

DOM

WebDriver conformance (Marionette)

  • Marionette will no longer be enabled unless the --marionette command line argument or the MOZ_MARIONETTE environment variable is specified. As such the marionette.enabled preference is no longer used. With this change the state of navigator.webdriver now correctly reflects the enabled state of Marionette (bug 1593343).
  • Fixed a bug where pointer actions other than down and up inappropriately led to buttons being pressed (bug 1686361).
  • Fixed a race condition in WebDriver:GetCurrentURL that could have led the command to return the URL of the previously opened page, or even a hang in Marionette (bug 1664881).

Changes for add-on developers

Older versions