Unexpected error when swtiching between code pane tabs

[AlexJerabek]

Bug Report

• Host: Excel
• OS: Windows
• Browser: win32
• Environment: Beta

Expected behavior:

Actual behavior:

Switching between the Libraries and Script tabs caused an unexcepted error (log below).

Steps to Reproduce:

1. Open a snippet
2. Rapidly switch between tabs in the code pane.

Failure Logs:

Script Lab
An unexpected error has occurred.
Unable to get property 'getText' of undefined or null reference

TypeError: Unable to get property 'getText' of undefined or null reference
at t.findDocumentLinks (https://script-lab-react-beta.azurewebsites.net/external/monaco-editor-0-16-2/vs/language/html/htmlWorker.js:7:328727)
at e.prototype.findDocumentLinks (https://script-lab-react-beta.azurewebsites.net/external/monaco-editor-0-16-2/vs/language/html/htmlWorker.js:7:340232)
at t.prototype.fmr (https://script-lab-react-beta.azurewebsites.net/external/monaco-editor-0-16-2/vs/base/worker/workerMain.js#html:141:1)
at e.prototype._handleMessage (https://script-lab-react-beta.azurewebsites.net/external/monaco-editor-0-16-2/vs/base/worker/workerMain.js#html:88:148)
at handleMessage (https://script-lab-react-beta.azurewebsites.net/external/monaco-editor-0-16-2/vs/base/worker/workerMain.js#html:87:691)
at e.prototype._handleMessage (https://script-lab-react-beta.azurewebsites.net/external/monaco-editor-0-16-2/vs/base/worker/workerMain.js#html:85:883)
at e.prototype.handleMessage (https://script-lab-react-beta.azurewebsites.net/external/monaco-editor-0-16-2/vs/base/worker/workerMain.js#html:85:394)
at e.prototype.onmessage (https://script-lab-react-beta.azurewebsites.net/external/monaco-editor-0-16-2/vs/base/worker/workerMain.js#html:87:764)
at self.onmessage (https://script-lab-react-beta.azurewebsites.net/external/monaco-editor-0-16-2/vs/base/worker/workerMain.js#html:142:382)

Screenshot:

[Zlatkovsky]

@AlexJerabek , is the issue intermittent, or is it happening all the time?

[AlexJerabek]

@Zlatkovsky I can cause the crash fairly consistently. It's more likely to happen when freshly loading Excel and Script Lab.

[Zlatkovsky]

@AlexJerabek , I believe this should be fixed with the deployment from an hour ago (whereby we upgraded to a newer version of Monaco, and should hopefully stop seeing those intermittent issues).