How can I get my WYSIWYG editor to stop *#@&%^ing up my HTML? I've tried every combination of "CLEANUP AND OUTPUT" settings that might conceivably prevent munging my HTML, but nothing works.  No matter, what, my HTML gets flattened or in some way rewritten, mainly with whitespace being trimmed off that I want to leave in.

I would suspect CKEditor (version 3.6.4.7575) except that when I tell WYSIWYG to "Apply source formatting", CKEditor doesn't prevent that, so it seems that logically this problem is in the WYSIWYG module.  "Apply source formatting" simply causes the HTML to be screwed up differently.  Some linebreaks are left in place, but spaces at the beginning of the line are left in place.

How can I prevent this, and still use a WYSIWYG editor?
I had just run into this problem of wysiwyg editors reformatting the html source into a minimized blob of contiguous html.    

The solution I found was to use TinyMCE editor with WYSIWYG and to add an additional module called wysiwyg-codemagic.  With this module, you place the codemagic plugin for TinyMCE in the TinyMCE library's plugins (Follow the instructions in module's Read.Me).  

Now, when the author of the node content drops into the html source, as occasionally needed, the source is very readable and presented correctly.

This was an old post, but I thought this new info would help for the others of us that still run into this problem