For 3.0 beta, when I invoke File>Import>Bookmarks>Safari the first time, no new group with bookmarks is created in my active database.
File>Import>Bookmarks>Google Chrome works.
I am running Mojave 10.14.4 and Safari 12.1 (14607.1.40.1.4).
My extensions:
When the application is stalled, do a Spotlight search for Activity Monitor . Select our application in the list of processes - it should show “(Not Responding)” and the name in red - and press Command-Option-S to run a sample on it. When the sample window opens, press the Save button and save it to your Desktop.
Hold the Option key and choose Help > Report bug to start a support ticket and attach the process sample to the email so we can inspect it. Thanks!