QB Issue Resolution:

I just installed the update released this morning and I am able to launch Layout Designer without the error, as well as update my invoice template which I desperately needed!

Resolution for Issue 'Quickbooks Mac 2019 Layout Designer App Crash' available: Yes (Solved).
Source: Intuit Community forum.

Quickbooks Mac 2019 Layout Designer App Crash: 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 App Crash
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Error Recovery for App Crash [Canada]
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