Opera 9.5 failed to process TinyMCE correctly. so if you enterd something in the HTML editor and came back to Visual editor mode.. you won’t see any text. Check out thses screen shots.

Actually it is caused by wrong implementation of JavaScript in TinyMCE. More about it is explained at opera development blog. In the race to win Acid3 test Opera made the implementation of web standards strict. It was this that caused the error.
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As of now the problem has been solved in Opera 9.51 and this post is being written using Opera 9.51. Another known issue with TinyMCE was scrabling of text when pressing the ENTER key. This is also solved now.
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