I would like to set the tinymce config to
valid_elements: "*[ * ]"
I noticed that the TinyMCE config changed now with the HTMLEditorConfig class and so I tried this instead in /mysite/_config.php:
HtmlEditorConfig::get('cms')->setOption('valid_elements', '*[ * ]');
I also tried
But it doesn't change. The browser cache is cleared, but something doesn't work yet, e.g. I can't add an <acronym> tag.
If anyone has an idea I would be keen to hear it.