Entering raw HTML in editors
From Joomla! Documentation
If you want to enter raw HTML in a Joomla! editor field, you may encounter problems such as tags and attributes disappearing after you save the item you are editing. This is usually caused by a filtering mechanism; either your editor's or Joomla!'s.
Global Text Editor Configuration[edit]
On the Administrator panel, take the following steps to disable filtering:
Disable Your Editor[edit]
Since each editor has its own filtering mechanism and it is not always possible to turn it off, disabling your editor is the easiest way of eliminating it as a possible source of the problem. Open your user configuration from the Administrator → Users menu. Select the Basic Settings tab. Change the Editor to Editor - None. Select Save & Close.
Disable Joomla's Filtering[edit]
Open the Global Configuration from the Site menu and go to the Text Filters tab. Set the Filter Type to No Filtering for the user group that you are in - Administrator, Super Users, or both (this is site-dependent). Caution: Do not use the No Filtering setting for user groups that are not fully trusted – that would introduce a sizeable security risk.
You should be able to enter raw HTML in any editor field now. You may try to re-enable your editor to see whether it influences the process. If the editor does mangle the HTML you are trying to enter, consult its documentation to see if there is a way to disable its filtering.
When the Text Editor in Use is TinyMCE[edit]
You may be able to make some adjustments to it and keep your WYSIWYG editor.
- Go to Administrator → Extensions → Plugins.
- Search for TinyMCE and open it for editing.
- Choose the Set 0 tab or whichever set has Super-Users or your desired user group.
- Scroll down to Prohibited Elements.
- Remove iframe (with its leading comma, if present) or whatever text you need to stop being prohibited.
- Select Save & Close.
Always be wary of doing this. Users may intentionally or unintentionally (hacked accounts) post something malicious which could affect your guests.