On: I spent some time exploring how to improve the UX ...

[alpaca128]

I hate that too, and it seems to be a very common default behaviour of text selection. Even Vim does it when you copy a whole line.

It's one of those little UI annoyances that refuse to disappear. Just like blinking cursors in unfocused input fields & windows.

[Someone → alpaca128]

I think that’s because, if you follow selection of a full line by a backspace/delete/cut, you expect the new line to disappear.

Apart from undo state, you also want cut to be equivalent to copy; backspace.

[arthur2e5 → alpaca128]

It probably ties into the whole “line ending not newline” philosophy of requiring files to end with an EOL character.