Heya!
Recently found an old post that remained unanswered because the solution for this bug is unknown, until now(?).
Basically the bug exists when turfs are not blinking on the Radar/Map and today I've found the solution/problem which is .NET framework being
outdated or it isn't working properly anymore with SAMP.
I installed this Windows update today and after 4 days of having this bug, it got fixed after rebooting the computer.
Cumulative Update for .NET Framework 3.5 and 4.8 for Windows 10 Version 1909 for x64 (KB4552931)
You can find the steps to install/update .NET framework on Google, there are plenty of sources which carefully explain the steps for all windows editions. Updating .NET Framework manually will probably
not work, so to get it fixed you need to get it updated through Windows Updates.
Keep this thread alive as some people may encounter this bug and can refer to this thread. You're allowed to post notes, comments and a confirmation if it's fixed.