[Bug]: Cannot change Ethereum Network settings

### Describe the bug

The networks pre-set by the Metamask browser extension cannot be edited. For example it's not possible on my machine to change the Ethereum RPC url. Mind-boggling.

Happens in Firefox and Brave, macOS.

### Steps to reproduce

1. Go into the network settings of your MetaMask browser extension.
2. Try to edit the RPC.
3. See it does not work.

### Error messages or log output

None.

### Version

10.22.1

### Build type

_No response_

### Browser

Firefox

### Operating system

MacOS

### Hardware wallet

_No response_

### Additional context

_No response_

No source file, test, or entry point is identified in the issue. First reproduce the problem in the MetaMask network settings using Firefox or Brave on macOS, then trace the Ethereum network editing flow; it is done when the preset network's RPC URL can be changed and the new value persists.

Written by the indexing model from the issue text.