Anybody who leaves ANYTHING visible in their car, at any time, no matter how innocent, is taking a risk. If you have a bag with powdered substances in it, even more so.
We can’t have that mentality. If they want to search your car, they’ll search it, whether you give them “consent” or not.
Here’s a guide that says “anything visible” can include a second cell phone, an air freshener hanging from the rear-view mirror, “too many” fast-food wrappers, or even a Bible.
https://www.icmag.com/ic/showthread.php?s=ea6871b93e6c52e337db2435a45e582f&t=171952
Also note in that same source that they might pull you over if you are driving below the speed limit, if your car looks better than it should for its age, or if you have a “support your local police” sticker.