Crash report: `TypeError: s.flatMap is not a function`

URL

https://swap.factorychain.io/#/swap?outputCurrency=0x8409cb3b54104ce63f7942a1403cc12c7e68b64e

swap state

{
  "independentField": "INPUT",
  "typedValue": "",
  "INPUT": {
    "currencyId": null
  },
  "OUTPUT": {
    "currencyId": null
  },
  "recipient": null
}

Error

TypeError: s.flatMap is not a function

Stacktrace

TypeError: s.flatMap is not a function
    at https://swap.factorychain.io/static/js/main.f5c03036.chunk.js:1:176187
    at Object.useMemo (https://swap.factorychain.io/static/js/3.b9a5ba8e.chunk.js:2:1660526)
    at push.t.useMemo (https://swap.factorychain.io/static/js/3.b9a5ba8e.chunk.js:2:1578796)
    at Fs (https://swap.factorychain.io/static/js/main.f5c03036.chunk.js:1:176165)
    at ud (https://swap.factorychain.io/static/js/main.f5c03036.chunk.js:1:182816)
    at push.790.S.maxHops (https://swap.factorychain.io/static/js/main.f5c03036.chunk.js:1:184943)
    at md (https://swap.factorychain.io/static/js/main.f5c03036.chunk.js:1:185337)
    at rC (https://swap.factorychain.io/static/js/main.f5c03036.chunk.js:1:583097)
    at oo (https://swap.factorychain.io/static/js/3.b9a5ba8e.chunk.js:2:1654561)
    at Wf (https://swap.factorychain.io/static/js/3.b9a5ba8e.chunk.js:2:1706861)

Device data

{
  "ua": "Mozilla/5.0 (Linux; Android 11; SM-A515F) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.152 Mobile Safari/537.36",
  "browser": {
    "name": "Chrome",
    "version": "88.0.4324.152",
    "major": "88"
  },
  "engine": {
    "name": "Blink",
    "version": "88.0.4324.152"
  },
  "os": {
    "name": "Android",
    "version": "11"
  },
  "device": {
    "vendor": "Samsung",
    "model": "SM-A515F",
    "type": "mobile"
  },
  "cpu": {}
}

Reproduce the crash at the reported swap URL using the supplied swap state, then trace the minified main.f5c03036.chunk.js stack around Fs, maxHops, and the useMemo call. Confirm the underlying source location and add coverage or a fix so this URL no longer throws the reported TypeError.