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Changes between Initial Version and Version 1 of Ticket #19437, comment 2

initial	v1
1	1	Been looking into something similar recently too. However to set anything into TinyMCE's iframe it has to go through JS (as it's 100% JS generated). So we need a JS "helper" function to modify classes (and IDs?) in the iframe document.
2	2
	3	Seems the best way to do this would be to handle it from one of our custom TinyMCE plugins: we can pass extra classes as MCE init setting and then apply them from the plugin.
	4
3	5	Also it seems we need to make editor-style.css more structured/predictable. There are styles/selectors that shouldn't go in there and all selectors should be exactly the same as in the theme's style.css.