Testing microsoft/vscode-jupyter#11463

• Open an ipynb notebook
• Take a screenshot, paste into a markdown cell
• Ctrl+Enter to turn the markdown cell into preview
• Double click the markdown cell to continue editing the cell, then delete the attachment link from the markdown cell
  🐛 Save the document. Then right click on the editor title bar, run Reopen Editor With ... to open in a text editor, please make sure the image attachment data is not in the file.