To be more specific, the issue isn't just opening the notes on your web browser. To reproduce it: Create a note with foo bar baz Edit it from the web. Close and open your evernote app on mac. You will see note going from formatted state to losing all bullet list indentation levels.
Recent premium user after using evernote free for 4 years and just ran into this issue where I used the evernote app for OSX and created a fairly lengthy note full of bulleted lists with varying degrees of indentation in sub-headings. All looked good and formatted to my liking, but as soon as I opened this note in the web browser (from a Linux machine where there is no evernote app) the whole indentation levels were lost. It went from something like: foo bar baz za za gabor to foo bar baz za