I haven’t been to Alaska, but I have some mosquito netting that slides over the top of my rear windows and that allows me to keep the windows down and the mosquitoes out.

https://www.amazon.com/dp/B088PF4WZK?ref=ppx_pop_mob_ap_share

Bears, I’m not too sure how to plan for. I’ve been places where they have black bears and have been able to get away with bear bags or bear boxes in campsites… but I’m told black bears are more timid than the bears up north…