@trilojan - I have an iPhone 5S, iPhone 6, iPhone 6s, iPhone 8 and iPhone X all on iOS 12.1.4 all still exhibiting this really annoying bug. Even if I don't scroll it, the favorites list re-arranges itself randomly after I save it - and even sometimes before I save it. Apple software quality and usability has really taken a big hit in the last few years and using Apple devices now is like I felt with Nokia devices in the last few years leading up to the initial iPhone introduction. Everything was so painfully complicated and buggy - the UX/UI folks lost touch with reality and how users use their phones and tried to make the phones do too much.
I thought iOS 12 was a good start towards focusing on fixing bugs rather than adding features, but it appears that Apple forgot what QA was/is! I doubt Steve Jobs would have allowed "Recents" be the title of the "Recent Calls" list in the phone app! Since when was "recents" even an English word? iOS is littered with these little text bugs - so I'm wondering what the source code looks like now...
What happened to focus on the user and simplicity in design? Come on Apple!