Closing off your airflow when refilling tanks. ???

[Coo1 Runn1ngs]

Heh, I must admit I'm a little perplexed too. "Micro changes in air density", indeed... (spot the obscure movie reference)

Not sure if the competitions still open but that was Ripley in Alien
Anyway, why I'm here, 3 years later reading this thread;
It would seem that manufacturers haven't yet found a one fits all solution as I'm having the same issue with a relatively new Smok Baby Prince with TFV8 mesh coil but haven't tried closing air holes yet. I did come across something in my search talking about changes in pressure but instead of a straw, they used a bird feeder bottle as an example where the water stays in the dish when the bottle is turned upside down because the empty space in the bottle forms a vacuum, if you were to poke a hole in the top, it would all spill out. Just thought that there's maybe something in that analogy.