Once you access the Horde Webmail client
click to "New message" button. Then you will see "Switch to HTML composition". Click it and a "WYSIWYG" editor will open, with options to edit text’s font, size, format, to insert links and images, etc.. make the changes as you want and then click on "Send Message" button.
Note : In some browsers "Switch to HTML composition" doesn't show properly. In such cases please check it with different web-browsers.
click to "New message" button. Then you will see "Switch to HTML composition". Click it and a "WYSIWYG" editor will open, with options to edit text’s font, size, format, to insert links and images, etc.. make the changes as you want and then click on "Send Message" button.
Note : In some browsers "Switch to HTML composition" doesn't show properly. In such cases please check it with different web-browsers.