More info:
STORE buttonSTORE -> ExploreSTORE againAlso i did this again, but waited bit more on explore page, store shows now, but it looks weird, no data at all.

I clicked F5 to refresh, but it shows black window again.
Ah, steam store index page is dead
Something to check is what IP address do you get for store.steampowered.com?
host store.steampowered.com
wget -O /dev/null https://store.steampowered.com
Hello @XakepSDK, are you still experiencing this issue on an up to date system?
Closing pending feedback.
Nothing extracted yet.
Your system information
Please describe your issue in as much detail as possible:
Sometimes store browser does not work.

It just shows black window. Browser works if i open library or community and click store again or click one of subitems in store dropdown.
Steps for reproducing this issue:
STORE