It did this for me yesterday in Firefox (normal mode) and then just started working after an hour. Currently the site looks normal for me just browsing normally or in private mode.
Looks like their nameservers are cloudflare so they may very well use cloudflare’s cdn:
clifford@Debian-Laptop:~$ host -t SOA level1techs.com
level1techs.com has SOA record jerome.ns.cloudflare.com. dns.cloudflare.com. 2028466459 10000 2400 604800 3600
edit: you could vpn to somewhere else and see if that fixes your problem which might be inidcative if it’s a cachin issue.
I use pfsense with snort an it will block externally hosted files if they are malformed. Happens quite often even on sites like yahoo (They have shitty js).