The coolant mixture does evaporate through the vent holes, but not very quickly in my experience.
Just to be on the safe side, especially if nothing is dripping on the ground, check the underside of the oil cap and the dipstick for oil consistency, if you see whitish, frothy residue, you may have a head or head gasket issue and coolant consumed by the engine.
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2018 Camaro 2SS — G7E MX0 NPP F55 IO6
735 rwhp | 665 rwtq
Magnuson TVS 2300 80mm pulley | Kooks 1 7/8" LT headers | JRE smooth idle terminator cam | LT4 FS & injectors | TSP forged pistons & rods
JMS PowerMAX | DSX flex fuel kit | Roto-Fab CAI | Soler 95mm LT5 TB | 1LE wheels | 1LE brakes | BMR rear cradle lockout | JRE custom tune
1100 - 1/30/18 | 2000 - 1/31/18
3000 - 2/06/18 TPW 2/26/18
3400 - 2/19/18 | 3800 - 2/26/18
4300 - 2/27/18 | 4B00 - 3/01/18
4200 - 3/05/18 | 4800 - 3/14/18
5000 - 3/16/18 | 6000 - 3/19/18
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