QB Issue Resolution:
QuickBooks Online does not provide individual spaces for each email address, but you do have the option to add multiple email addresses by using a comma and space before the next email address.
Resolution for Issue 'QBO: Email invoice to two different email addresses' available: Yes (Solved).
Source: Intuit Community forum.
QBO: Email invoice to two different email addresses: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for Email Invoice
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Error Recovery for Email Invoice [Canada]
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