Website doesn’t load in Firefox but works in Chrome and Edge

Hello, I’m experiencing an issue where my website https://smartstartkids.com.ua doesn’t load at all in Firefox. When I try to open it, nothing happens or I get a message like “The connection was reset” or “Network error”. The strange thing is that it works perfectly in Chrome and Microsoft Edge on the same devices and network. Here’s what I’ve already tried: • Cleared Firefox cache and cookies • Created a new Firefox profile using firefox.exe -P • Disabled and fully uninstalled ESET antivirus • Turned off Windows Firewall • Reset DNS and Winsock via Command Prompt (ipconfig /flushdns, netsh winsock reset) • Checked proxy settings (set to “No proxy”) • Tried with HTTP3 disabled (network.http.http3.enabled = false) • Tried from two different PCs and networks — same result • The certificate shown is from “Sectigo”, not ESET, so it seems to be correct now Still, Firefox is the only browser where this specific site doesn’t load. I’d appreciate any ideas or help! Thank you!