Seconding raindrop.io. Went from being a tab hoarders with Tab Outliner, but the extension finally broke and isn't supported. Thankfully I managed to import my huge list by munging the JSON file into a CSV. Hate that it's stored on the cloud, but I just export it out into CSV so if I have to move again I can. That said the autotagging and recommendations are great. I have a ton of tabs I didn't organize and it automatically suggests folders to move them to that are correct 99% of the time.

I would mention how many tabs I migrated to highlight how good the performance is, but I'm embarrassed to admit how many I saved...