# Moodle Upgrade notes This file contains important information for developers on changes to the Moodle codebase. More detailed information on key changes can be found in the [Developer update notes](https://moodledev.io/docs/devupdate) for your version of Moodle. The format of this change log follows the advice given at [Keep a CHANGELOG](https://keepachangelog.com). ## 4.5.13+ ### core #### Changed - The title of a modal dialogue rendered by the `core/modal` template is now an `

` element instead of an `

`, so that dialogue titles no longer break the page's heading hierarchy for assistive technology users. The element carries the Bootstrap `h5` typography utility class, so the title's appearance is unchanged. If your plugin renders headings inside modal dialogue content, set their levels relative to this `

` (i.e. start at `

`) so that the heading structure remains correctly nested. Headings that were previously nested beneath the old `

` will now skip levels. If your plugin renders its own modal header markup, or overrides the `header` block of the `core/modal` template, apply the same `