Unable to access instance's editor in Safari

### Current Behavior

After creating a Node-RED v4 instance, I cannot access the editor using the Safari browser. Instead, unauthorised error is presented. Please take a look at the attached video (the video presents the accessing editor for the instances running on different NR versions as well).

https://github.com/user-attachments/assets/daa549d2-7fe7-4157-a5f4-6ac2bb07e6b8

### Expected Behavior

I should be able to access Node-RED instance using Safari browser.

### Steps To Reproduce

1. Create an instance with Node-RED version 4.0.2
2. Once it becomes ready, try accessing the editor using the `Open Editor` button

### Environment

- FlowFuse version: FlowFuse Cloud
- Node.js version: n/a
- npm version: n/a
- Platform/OS: n/a
- Browser: Safari (17.6 (19618.3.11.11.5))

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate