To identify the cause of this issue, we had started our investigation with the aim to resolve it. You might have also received email from us seeking more details to help in our investigation.

We’ve concluded our investigation and came up with the finding : Either the issue is fixed in the latest release of InDesign or the issue was intermittent in nature at the time of its reporting and is not reproducible now.

We recommend you to upgrade to the latest version of InDesign 2020 (if you’re not already on it). It contains a lot of stability fixes.

If you still face this issue even after updating to the latest version of InDesign, please submit the crash report to us. (The guidelines to submit crash are available at (https://helpx.adobe.com/indesign/kb/submit-crash-reports.html)
We seek your support in our continual effort to improve InDesign.

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Adobe InDesign Team

We have released InDesign 2020.0.1 with a lot of stability fixes. We recommend you to upgrade to latest version (if you’re not already on it) as it is more robust.

If you still face this issue even after updating, please submit the crash report to us. (Guidelines to submit crash are available at (https://helpx.adobe.com/indesign/kb/submit-crash-reports.html)

Also, please send the following information to santalwa@adobe.com:
• Reproducible Steps – What were you doing when InDesign crashed?
• Video recording of the crash?
• Is(Are) the issue related to a specific document(s)/asset(s)? If yes, could you provide the document(s)/asset(s) to us? Please package the entire document (To package the document, choose File → Package…)

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Adobe InDesign Team

My InDesign is with the same issue. I'm trying to save as IDML, but it closes suddenly.

Aman I had the same issue and did as you recommended and then saved the IDML file back as INDD format and no issues.