I just checked it with the emulator. After pressing the HELP key twice, nothing works in the editor.
So I'm not the only one who repeatedly taps the HELP key in desperation! I've created a small fix. (Could be nice if this forum accepted a d81 file extension). The same bug happens with function keys too. A `KEY OFF` before doing `GETKEY` (and then a `KEY ON` afterwards) will tell the function and HELP keys to return their keycode instead of whatever text they print out.