FIXED
The problem was in Ezoic. I have integrated Ezoic via Cloudflare. And I saw in the NETWORK under Chrome developer tools *gif files from ezoic, that were taking long to load. This files were preventing content to load only in INCOGNITO Chrome and only in categories. In normal mode everything was loading as it should.
The weirdest thing was that INCOGNITO mode in Chrome and Safari was caching the site. I thought Incognito will never cache the site.
– the developer mode in cloudflare was enabled
– cache was purged in cloudflare and ezoic as well
– I have deleted all the browsing history/cookies/cache from browser
– tested it on 2 different machines
– I have even reinstalled chrome
Anyways thanks for your help.