System: Mac OSX Leopard 10.5.7 all current patches on MacBook Pro
After upgrading to 1.3.20, every operation which inserts a new entry results in a "spinning wheel" rendering the computer useless. No operation possible except switching manually off. Sometimes it happens during filling out the key of the new entry, sometimes it proceeds until the new entry is displayed in the latex preview. No crash report possible since the sysrtem does not react to any other input any more when it happens. It happens reproducible every time.