This above!
Try not to give her too much thought if you can.
You can be strong in yourself without being confrontational and feeding in to her unhealthy behaviour repetition.
Also it’s good to keep your body language relaxed but confident.
out of sight out of mind helps you both if it’s practical and doable.
It’s always good to play save with unknowns and not fall into unhealthy behaviour yourself.
You don’t want a stranger having some emotionally negative impact over your day, she’s not important but might want you to make her feel so by soliciting a response at her creation.
Some individuals fall into looking for that feel of cause and effect to feel something they need.
Try not to fall into wondering about her motives, or making assumptions about her, just focus on yourself and your goal of staying calm, focused and relaxed if it happens again, a simple internal mantra like a happy “f*ck it” might help, you choose what helps.
Remember OP:
You are important in this world and do a lot of good I’m sure without even realising it. Don’t let this incident distract you from feeling good about yourself. Life is challenging enough right now without superfluous distractions. That’s all she is, an unhealthy superfluous distraction if that helps?
Good luck OP