Insight Issue: Duplicate values due to whitespace replaced with underscore on custom dimensions

[DanielStormApps]

This issue was recently resolved for default dimension values, majorSystemVersion for example, here: https://github.com/TelemetryDeck/Issues/issues/340

Unfortunately, this issue is still present for all my custom dimension values, applicationName is declared by me on my events in this example.

This is occurring across all my custom dimension values, not just applicationName, which results in inaccurate data across all insights reliant on custom dimensions.

Insight ID: B56C46B1-2937-4EFA-9C58-24D395B91C8E

{
  "aggregations": [
    {
      "fieldName": "clientUser",
      "name": "count",
      "type": "thetaSketch"
    }
  ],
  "baseFilters": "thisOrganization",
  "dimension": {
    "dimension": "applicationName",
    "outputName": "applicationName",
    "type": "default"
  },
  "filter": {
    "field": {
      "dimension": "applicationName",
      "type": "selector",
      "value": ""
    },
    "type": "not"
  },
  "granularity": "all",
  "metric": {
    "metric": "count",
    "type": "numeric"
  },
  "queryType": "topN",
  "threshold": 200
}