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Here in Sweden, a Trangia burner costs about $15, so taking a new one every trip could be an option. ....
In most cases the security inspectors will do the smell test, if they smell residual fuel it gets confiscated. But if your stove is an alcohol stove, keep in mind that alcohol is infinitely soluble in water, so a good water bath should make any trace of smell disappear.
But, you never know if you will get an overly cautious inspector, apparently some confiscate all stoves they find unless they are in new packaging. They are in a work environment where they are unlikely to get in trouble if they are overly stringent.