'supabase-js' client's channel.subscribe() always returns state 'CHANNEL_ERROR'

[lht1324]

Bug report

• [✅] I confirm this is a bug with Supabase, not with my own application.
• [✅] I confirm I have searched the Docs, GitHub Discussions, and Discord.

Describe the bug

I made codes which uses Supabase client's channel by following the docs, but it always return the state 'CHANNEL_ERROR'.

To Reproduce

I couldn't find the exact conditions that cause the error. I'm just guessing that it happens in certain versions greater than 2.50.x.

Expected behavior

this.socket = new this.params.WebSocket(url, undefined);

AI said that 'undefined' makes 'Sec-WebSocket-Protocol: undefined' header, so connection was closed before hand-shaking. Just remove 'undefined' in WebSocket().

This temporary solution worked for me.

Screenshots

If applicable, add screenshots to help explain your problem.

System information

• OS: Windows 10 Home
• Browser: chrome
• Version of @supabase/supabase-js: 2.50.2
• Version of Node.js: 20.17.57

Additional context

I got this solution from AI, and thought its solution a hallucination, but it worked. AI said that this error is solved in your internal branch, v2.53.1.

[georgRusanov]

Hello
The current latest version is 2.50.2. There is no tag 2.53.1.
You are expecting that new this.params.WebSocket(url, undefined); should work, am I correct?

[lht1324]

Nope. I don't know how it worked, but AI suggested the solution in that pic. That's why I wrote this.

AI said that there are new this.params.WebSocket(url, undefined); somewhere in Realtime codes, and that undefined cut hand-shaking by making Sec-WebSocket-Protocol: undefined header.

AI said that it was solved in Supabase's internal version 2.53.1. I thought it may be a hallucination, but the solution worked, so I posted that just in case.