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Select the address with mouse, then click-and-drag it to where you want to paste it.
I'm sure you meant
this way, and yes I did too. But as a fact it doesn't support in some apps including notepad and some web pages.
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Obviously, it's not advisable to keep important stuff in random text files, and I would never do that, but, erm... I have a friend who does it all the time.
As long as you can confirm your own actions (provided you also understand wallet security) and have proven up to this point that nothing happened, then go ahead. It's meant only to show your habits, not to recommend others.