API browser can display API differences between different versions

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**Issue moved from MicrosoftDocs/feedback#3517**
- Please respond to @raven15.

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_From @raven15 on Thursday, February 25, 2021 7:56:08 AM_

**Is your feature request related to a problem? Please describe.**
API differences between different versions or frameworks cannot be compared。

**Describe the solution you'd like**
This is very useful for developers who are familiar with the old version of API. Every time we update the version, we can easily understand the API changes brought by this upgrade.

It can also increase the contrast between different frameworks. This is also great for developers who want to migrate from the. Net framework platform to the. Net core platform.

It can intuitively show how many APIs have been changed, how they have been changed, and what they have been changed under some namespace or class.

| Added +10 | Disuse -1 | Improved ^50 |

Hope it can be adopted! Thank you!

**Describe alternatives you've considered**
If the official does not support this idea, and if there are developers in the community with this idea, we can explore whether we can try to implement it in the form of browser plug-ins。

**Additional context**