Bookmarks manager broken in 12.0a2 on MacOS

A forum user has reported that they cannot import bookmarks using 12.0a2 on MacOS. On investigation it looks like the entire bookmarks manager is bugged out – with the window reading the following error:

bookmarks-error-120a2

To reproduce, click Bookmarks > Manage Bookmarks. Could someone check to see if this is MacOS specific, or occurs on other platforms too?

Edited by donuts