Unable to add Audit history under Opportunity Object

Summary:

Hi,

We are trying to add the Audit History component to the Opportunity Detail page by following Oracle documentation. However, the Code tab is not available for the Opportunity page. Instead, the following message is displayed:

"Base application code cannot be viewed from an extension."

Interestingly, the Code tab is available for other standard objects such as:

Account

Contact

Lead

Only the Opportunity object does not allow access to the code. Why it is not enabled

Any help on this is highly appreciated.

Thanks,

Seetha

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