I also have the same issue in Firefox, Chromium and Vivaldi on Linux. I tried searching the interweb for a cause/fix, but couldn't find anything sensible in th

I also have the same issue in Firefox, Chromium and Vivaldi on Linux. I tried searching the interweb for a cause/fix, but couldn't find anything sensible in the flood of low-quality SEO hijacking webcrap returned by multiple search engines. So I asked AI. The claim is that it could be caused by the blocking of some DNS providers (NextDNS, Quad9, ..), and it suggested using a VPN or phone tethering. And lo and behold, both suggestions worked, without any browser setting changes. It's very annoying and inconvenient.