thats an virus, my defender said the .rar have Trojan:Win32/Pomal!rfn and Trojan:Win32/Wacatac.B!ml on some clients, i think its on the 2020 and 2021 clients, idk if thats real, yeah i did again this comment
Do not worry, I used to run old Roblox clients. This is just a side effect of them being meant for older Windows versions, a false positive, but note it may not apply to all clients since there are unofficial binaries---possibly with malware.