Do you mean when trying to copy test from a forum post? If so, yes I just reproduced it using this exact post. Please use the report a bug feature and report this. It's an issue with the z-index.
Text selection problem
I will do so if you like, but it looks as though you might be able to give them some useful information to help them fix it. Would you do it?
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Have other people noticed the problem in V3 at the moment where often if you try to select text, it selects the wrong text?