TinyMCE editor
From MoodleDocs
The popular TinyMCE editor can be enabled, disabled or set as default from Administration > Site administration > Plugins > Text editors > Manage editors.
If enable, users may select the TinyMCE editor from the user menu top right>Preferences>Editor preferences
Note: an earlier version, the TinyMCE editor (legacy) is also available, although it is recommended to disable it if you plan to use the newer version.