Context file not written when using multiple localfilesystem entries

On a later re-run I did get an error - but related to the flow variable to the file context store:

Welcome to Node-RED
===================
6 Dec 22:18:29 - [info] Node-RED version: v3.0.2
6 Dec 22:18:29 - [info] Node.js  version: v16.18.1
6 Dec 22:18:29 - [info] Linux 5.15.74.2-microsoft-standard-WSL2 x64 LE
6 Dec 22:18:29 - [info] Loading palette nodes
6 Dec 22:18:29 - [info] Settings file  : /home/julian/nrlive/data/settings.js
6 Dec 22:18:29 - [info] HTTP Static    : /home/julian/nrlive/public > /
6 Dec 22:18:29 - [info] Context store  : 'default' [module=memory]
6 Dec 22:18:29 - [info] Context store  : 'file' [module=localfilesystem]
6 Dec 22:18:29 - [info] Context store  : 'altFile' [module=localfilesystem]
6 Dec 22:18:29 - [info] User directory : /home/julian/nrlive/data
6 Dec 22:18:29 - [warn] Projects disabled : editorTheme.projects.enabled=false
6 Dec 22:18:29 - [info] Flows file     : /home/julian/nrlive/data/flows.json
6 Dec 22:18:29 - [info] Server now running at http://127.0.0.1:1881/red/
6 Dec 22:18:29 - [info] Starting flows
6 Dec 22:18:29 - [info] Started flows
6 Dec 22:18:49 - [info] Stopping flows
6 Dec 22:18:49 - [info] Stopped flows
6 Dec 22:18:49 - [info] Updated flows
6 Dec 22:18:49 - [info] Starting flows
6 Dec 22:18:49 - [info] Started flows
6 Dec 22:19:22 - [error] Error writing context: Error: ENOENT: no such file or directory, rename '/home/julian/nrlive/data/context/8f633713fe222323/flow.json.1670365162017.tmp' -> '/home/julian/nrlive/data/context/8f633713fe222323/flow.json'

And here is what I found in the file:

{
    "test2": "This is the file store - a flow var"
}    "test3": "This is the altFile store - a flow var - 2"
}

Oops!

I had changed the node-red settings to this (and restarted):

    contextStorage: {
        default: {
            module:'memory',
        },
        file: {
            module: 'localfilesystem',
            // config: {
            //     flushInterval: '10', // default is 30s
            // },
        },
        altFile: { 
            module: 'localfilesystem', 
            dir: '/home/julian/nrAltFileStore',
            base: 'context',
            cache: false,
            flushInterval: 1,
        }
    },