Extensions Plugin Manager Edit Button Group
From Joomla! Documentation
Editors-Extended Group[edit]
These plugins add items to the CMS Content drop-down list in the TinyMCE editor.
Button - Article[edit]
Displays a button to insert links to articles into an Article. Displays a popup allowing you to choose the article. This plugin has no options.
Button - Contact[edit]
Displays a button to insert links to Contacts in an article. Displays a popup allowing you to choose the contact. This plugin has no options.
Button - Field[edit]
Displays a button to insert a custom field into an editor area. Displays a popup allowing you to choose the field. This plugin has no options. Warning!: the custom field will not be rendered if the Content - Fields plugin is not enabled.
Button - Image[edit]
Displays a button to insert images into an Article. Displays a popup allowing you to configure an image's properties and upload new image files. This plugin has no options.
Button - Menu[edit]
Displays a button to insert menu item links into an Article. Displays a popup allowing you to choose the menu item. This plugin has no options.
Button - Module[edit]
Displays a button to insert a module into an Article. Displays a popup allowing you to choose the module. This plugin has no options.
Button - Page Break[edit]
This plugin displays the Pagebreak button below the editor box when you are using a Joomla! editor (for example, when writing an Article). It inserts a page break in the Article. This plugin has no options.
Button - Readmore[edit]
This plugin displays the "Read more..." button below the editor box when you are using a Joomla! editor (for example, when writing an Article). It inserts a "Read more..." break in the Article that allows you to display just the first portion of an Article on a page. This plugin has no options.