To turn off the "Based on recent edits" stuff, go to turn off IntelliCode suggestions.

Per the docs:

If you wish to turn it off, choose Tools > Options, IntelliCode General tab, and then switch C# suggestions to Disabled

This will turn off "Based on Recent edits" while still leaving on the other stuff like code styles/autocomplete/etc.

How to hide Intellisense “based on recent edits” suggestions?

If you want to hide such suggestion in Intellisense(show as a dot), you should add this below on the top of every cs file:

#pragma warning disable xxx(suggestion ID)

Or use #pragma warning disable to disable every suggestion.

For an example, I have make a similar sample:

================================================================

And usually to remove that Intellisense Suggestion, you should enter Tools-->Options-->Text Editor-->C#-->Code Style and then find such suggestion message and change its Severity from Suggestion to Refactoring Only. With this, you could remove such Suggestion on Code Editor.

Since I did not know your specific suggestion message(based on recent edits) and the ID and also not sure whether such suggestion are in the Code Style menu, so I suggest you could try my first solution.

Note that: So far, no matter which way you suppress the suggestion, removing dot in the Code Editor will also remove the message in the Error List. They are unified, you cannot suppress the IntelliSense in the Code Editor and save the message in the Error List.

Besides, if you still want this,you could suggest a feature on our User Voice Forum.