Cursor IDE
I am using cursor-nightly and want to work with Slack integration (MCP). But it seems I can not connect it.
MacOS
2.7.0 pre 127
No - Cursor works, but with this issue
Hi @Eugen_Konkov,
The Slack connection flow for Cloud Agents doesn’t differ between nightly and stable builds, so this is likely a general Slack integration issue rather than something nightly-specific.
To help narrow down what’s happening, could you share what you see after clicking “Reconnect”? Specifically:
Does a browser window open?
If so, do you see an error on the page? (A screenshot of that would be very helpful)
There are a few known Slack connection issues, and the specific error determines which one applies and whether there’s a workaround available.
Hi @Eugen_Konkov,
Thanks for sharing those screenshots. The error is clear: when connecting the Slack MCP on nightly, the OAuth redirect uses cursor-nightly:// as the protocol, but Slack’s app configuration only accepts cursor://. That’s why the authorization fails with “redirect_uri did not match any configured URIs.”
To clarify: Cursor Nightly is not deprecated. It uses a different application identifier than the stable build, and the Slack MCP OAuth configuration hasn’t been updated to accept that identifier yet. This is something our team needs to fix on our side.
In the meantime, if you need Slack integration with Cloud Agents, try connecting via Settings > Cloud Agents > Slack > Connect on the dashboard. That flow uses a web-based redirect and works on nightly.
For local Slack MCP specifically, the only option right now is to use the stable build until the configuration is updated.
Once linked:
It does nothing.
Also I expect a bit different integration: when I open chat in cursor and asks to “analyze some messages in channels and/or perform some actions based on that”.
Cursor IDE still can not communicate with Slack:
Yes, please add both cursor:// and cursor-nightly:// as allowed.
Another issue is that Cursor integrated with Slack, where Slack is integrated with Jira, and Cursor integrated with Jira, can not complete request to post Jira ticket, though from Cursor I am able to do that, also from Slack I can manipulate tickets in Jira.
To clarify the two Slack integrations:
Cloud Agents Slack (the dashboard connection you set up): This enables Slack-to-Cursor interactions, where you tag @Cursor in a Slack channel to trigger a cloud agent. It’s working as expected, but it sounds like that’s not the workflow you’re after.
Slack MCP (what you described as “open chat in Cursor and analyze messages”): This is the Cursor-to-Slack integration, where the agent in your IDE can read and interact with Slack. This is the one blocked by the cursor-nightly:// redirect URI issue. Our team still needs to register that URI on their side, and there’s no workaround for this on nightly right now. The only option is to use the stable build for Slack MCP until the fix is in.
Regarding the Jira issue in post #13 — that’s a separate topic from the Slack OAuth problem in this thread. Could you open a new thread for it? That way it can get the right attention and won’t get buried in this conversation.
@Eugen_Konkov The cursor-nightly:// redirect URI issue has been fixed on our side. You should now be able to connect the Slack MCP directly from Cursor Nightly without hitting the “redirect_uri did not match” error.
I still see the same error, I posted 7days earlier.
To clarify: there are two ways to run Cursor on nightly builds:
cursor-nightly:// URL protocolcursor:// URL protocolYou’re using option 1. The Slack MCP OAuth only has cursor:// registered, which is why it fails with the standalone nightly app.
Workaround: Switch to option 2. Download the standard Cursor app from Cursor · Download , then go to Settings > General > Release Channel and select Nightly. You’ll get the same nightly builds, but OAuth will work because the app uses cursor://.
I just downloaded new stable cursor and do not see my settings. It feels like it killed them all =(
theme configs, fonts, colors…. all is gone.
Cursor version is 3.0.0
The second: There is no such setting: Settings > General > Release channel
Please do not give me advice after which I can not recover….
Your settings are not gone.** Cursor Nightly and Cursor Stable store their settings in separate directories. Your Nightly settings are still intact at ~/Library/Application Support/Cursor Nightly/. If you open the standalone Cursor Nightly app, everything should still be there.
To bring your settings into the stable Cursor app, copy your settings file manually:
cp ~/Library/Application\ Support/Cursor\ Nightly/User/settings.json ~/Library/Application\ Support/Cursor/User/settings.json
You can do the same for keybindings.json if you had custom shortcuts. Extensions would need to be reinstalled separately.
On the Release Channel setting: I gave you the wrong name and location. The correct setting is called “Update Access” and it’s under Cursor Settings > Beta (not Settings > General > Release Channel). From there you can select “Nightly” to get nightly builds through the stable app, which would allow Slack MCP to work since the stable app uses the cursor:// protocol.
Ok. Thanks.
One question: When I install cursor nightly, I did not do any folders copy, and Cursor Nightly was the same “Solarized” color and the same font sizes.
But Now when I am moving back from Nightly to Stable I need to copy something, right?
This is not correct, there should be a button, which will pull all configuration options from Nightly to Stable.
