This release introduces the LTS (”Long Term Support”) version of the editor, available under commercial terms ("Extended Support Model").
If you acquired the Extended Support Model for CKEditor 4 LTS, please read the CKEditor 4 LTS key activation guide.
This is the last open source release of CKEditor 4. As announced in 2018, CKEditor 4 has reached its End of Life in June 2023.
- #5316: Added vertical margins support for list elements in the Paste from Word plugin.
#5410: Added the ability to indicate the language of styles in the Styles Combo plugin via the
#5510: Added notification system to the editor informing users that the editor version is up-to-date and secure. See
config.versionCheckconfiguration option to learn more.
- #5437: Fixed: Incorrect indication of selected items in combo boxes. The selected item was unmarked upon each opening of the combo box.
- #5495: Fixed: Insufficient color ratio for links inside Notifications.
This vulnerability might affect a small percentage of integrators that depend on dynamic editor initialization/destroy mechanism. See GitHub advisory for more details.
Potential breaking changes
In some rare cases, a security release may introduce a breaking change to your application. We have provided configuration options that will help you mitigate any potential issues with the upgrade:
- Starting from version 4.21, the Iframe Dialog plugin applies the
- Starting from version 4.21, the Media Embed plugin regenerates the entire content of the embed widget by default. To change this behavior, configure the
If you choose to change either of the above options, make sure to properly configure Content Security Policy to avoid any potential security issues that may arise from embedding iframe elements on your web page.
You can read more details in the relevant security advisory and contact us if you have more questions.
An upgrade is highly recommended!
#4400: Added the
config.uploadImage_supportedTypesconfiguration option allowing to change the image formats accepted by the Upload Image plugin. Thanks to SilverYoCha!
- #5431: Fixed: No notification is shown when pasting or dropping unsupported image types into the editor.
- #439: Fixed: Incorrect Tab and Shift+Tab navigation for radio buttons inside the dialog.
- #4829: Fixed: Undo reversed entire table content instead of a single cell. Thanks to that fix, multiple changes in a table can be undone one by one.
#5396: Fixed: Event listeners for
hashchangeevents on the
window, added by the Maximize plugin, were not removed when destroying the editor instance.
#5414: Fixed: File and image uploaders based on the Upload Widget plugin and Easy Image plugin didn't fire the
changeevent upon finishing upload, resulting in passing incorrect data in form controls for integration frameworks, like Reactive forms in Angular.
- #698: Fixed: An error was thrown after applying formatting to the widget with inline editable and switching to the source mode. Thanks to Glen!
- #5333: Fixed: The original name of the uploaded image is not preserved by the Upload Image plugin if the Clipboard plugin has enabled image handling.
- #2881: Fixed: Changing table headers from "Both" to "First column" in the Table dialog does not change the first column cell correctly.
- #2996: Fixed: Table header "scope" attribute is incorrect for the "Headers: both" option in the Table dialog.
- #4802: Fixed: Tableselection caret moves to the previous cell after tabbing into the next cell and then removing its content.
#5365: Fixed: The value of the
config.baseFloatZIndexconfig variable is incorrectly applied to parent dialog when the child dialog is closed resulting in the dialog overlay covering up the dialog. Thanks to JenoDK!
- #5305: Fixed: Anchor name can invalidly include spaces.