I liked the UI of BitBucket more. Stuff I accessed frequently like commits and branches were tabs across the top, easy to reach from any page. Branch dropdown sort order was by most recently updated unlike GitHub where I have to search for it. Easy to diff files. This was like 4 or 5 years ago though, maybe it has gone through modernization/enshittification. GitHub feels a bit fragmented and it tries to be more performant by virtualizing some things but while BitBucket in some sense was more rudimentary and showed it all (bogging my machine down some), it allowed me to CTRL + F easily with more confidence whereas with virtualization I've had issues with it finding things and I couldn't 100% trust it.