Try not to stare at smokes/double doors. Most people/pros do this and gets flashed, don't be like most people 😃👍
It depends on a few things, so this tip is a bit misleading. The depth of the smoke is important, which is usually determined by which team threw it. For example, if there's a smoke on Haven double doors and it's sticking way out towards you because it's flush on the other side, any player with a flash can pop out of it at any number of angles so it's impossible to prefire it. If it's flush towards you, it's unlikely to get pushed through, and even if someone pushes through it, it is easy to prefire it off of audio or just strafe away. The moral of the story here is to just not hold wide angles, hold somewhere you can easily fall back from unless you're Chamber, Jett, or a really confident Reyna.