Overview:
No Compare option available in the Version History of a Vault document.
Root Cause:
The document does not have multiple source versions uploaded.
Solution:
A document has multiple versions. The source documents have not been uploaded to all versions.
Example:
Version 0.2 has the compare icon while version 0.1 does not. The reason is that version 0.1 is a placeholder and holds no content.
Related Documentation:
Vault Help Documentation: Comparing Documents
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