The issue where Threads profile pictures don't show or update properly has several documented fixes, ranging from simple app setting adjustments to using specialized third-party tools for viewing. Quick Fixes for Profile Picture Display
: Issues with blurry thumbnails have largely been addressed, though saving images as high-quality JPEGs or PNGs is still recommended for your own profile to ensure clarity. threads profile picture viewer fixed
If you are using the desktop version, security extensions like Bitdefender Anti-Tracker The issue where Threads profile pictures don't show