Thanks for your report.
Though, I do not think that WinSCP ever accesses the Favorites folder.
Also there's no change between 6.5.5 and 6.5.4 that affects access to any folders whatsoever.
It rather looks like some kind of false positive.
Can you share details of the detection?
If you want us to investigate further, can you send me an email, so I can send you back a debug version of WinSCP to track the problem? Please include a link back to this topic in your email. Also note in this topic that you have sent the email. Thanks.

I am working with Windows 10 Pro (22H2) and with the newest Version always.
I updated from a direct previous version to 6.5.5 today Nov.24, 2025.
After updating to WinSCP [6.5.5] and restarting it, the program attempts to make changes in the folder %userprofile%\Favorites. My system protection blocks this, since the folder is protected. The Favorites/Location Profiles feature is not configurable, and even after switching to INI file storage, WinSCP still accesses the Windows Favorites folder. This behavior appears to be a bug. Please investigate and correct it.