How we can reproduce it:
1 Create new projecr
2 Go to Project Browser and type "new" in search field
3 Switch between "In Packages" and "In Assets" for the search results couple of times (sometimes you need to switch up to 10 times)
Actual results: error appear in Console:
"Request error (error):
UnityEditor.AsyncHTTPClient:Done (UnityEditor.AsyncHTTPClient/State,int)"
Editor.log has:
"Request error (error):
UnityEngine.StackTraceUtility:ExtractStackTrace ()
UnityEngine.DebugLogHandler:LogFormat (UnityEngine.LogType,UnityEngine.Object,string,object[])
UnityEngine.Logger:Log (UnityEngine.LogType,object)
UnityEngine.Debug:LogError (object)
UnityEditor.AssetStoreClient:ParseContent (UnityEditor.IAsyncHTTPClient)
UnityEditor.AssetStoreClient/<>c__DisplayClass45_0:<WrapJsonCallback>b__0 (UnityEditor.IAsyncHTTPClient)
UnityEditor.AsyncHTTPClient:Done (UnityEditor.AsyncHTTPClient/State,int)
Error performing Asset Store search: temporary searchd error: server maxed out, retry in a second"

Reproduces on:
2020.2.0a3, 2020.2.0a4, 2020.2.0a7, 2020.2.0a9
2020.1.0a25, 2020.1.0b2, 2020.1.0b7
2019.3.5f1
2018.4.0f1

please see .gif in comments