Got it — I confirmed your URL is exactly https://firstprinciples.zeabur.app (correct), and we just tested again from our side and it loads fine (HTTP 200 with valid SSL cert). So the URL is right, the server is right, the cert is right.
The SSL_ERR_RX_RECORD_TOO_LONG / ERR_SSL_PROTOCOL_ERROR appearing only on your machine in 3 browsers means it's a client-side / network issue, not Zeabur's. Things that could cause this when the server is fine:
Most likely causes (please try in order):
1. Antivirus or firewall doing SSL inspection ⚠️
This is the #1 cause when "all browsers fail but the site works for everyone else". Some antivirus software (Avast, AVG, Kaspersky, ESET, BitDefender) and corporate firewalls intercept HTTPS to scan it, but their fake cert/decryption can mangle the response into RX_RECORD_TOO_LONG.
→ Try temporarily disabling your antivirus's "HTTPS scanning" / "SSL inspection" / "Web shield" feature, then refresh. If the page loads, that's the culprit.
2. Corporate / school / coffee-shop network
Same as above but at the network level — some networks intercept HTTPS for content filtering.
→ Try switching to your phone's mobile hotspot (4G/5G). If the site works on hotspot, your current network is intercepting traffic.
3. VPN / proxy / DNS-over-HTTPS
→ Disable any VPN you have running, disable browser-level proxy settings, disable DoH temporarily
4. System-level issue
- Check your laptop's date/time is correct (off by hours = TLS rejects)
- Try a different device entirely (your phone on cellular). If it works on phone but not laptop → laptop has the issue, not network.
Diagnostic to confirm where the problem is:
Open Terminal/Command Prompt on your laptop and run:
curl -v https://firstprinciples.zeabur.app 2>&1 | head -30
If curl ALSO fails with TLS error → it's your laptop / network (not browser).
If curl WORKS but browsers fail → it's browser-specific (extensions, cache, etc.).
Paste the curl output here and I can pinpoint exactly which layer is breaking the connection. From our side everything's confirmed working, so we just need to find which layer between you and us is interfering.