User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:58.0) Gecko/20100101 Firefox/58.0 Build ID: 20180130172505 Steps to reproduce: I tried to remove all entries pointing to an invalid domain from chronik. Therefore I searches the domain, in the list window marked all ([ctrl]+[a]) and hit [del]. The Window showed something about 11.000 entries and Firefox got in medtation state. some seconds later the 'script busy' message appears... Actual results: ... i clicked continue and after some seconds the message reappeared... After a few rounds like this I killed Firefox and looked again to the chronik. A few hundreds entries less of that domain. I calculated the speed, the result of deletion speed is about 2 or 3 items per second. Expected results: Deletion of a few thousand entries should be done within a second or less compared to similar processes. Even if the deletion takes some seconds, the main Window should respond and should be usable to work on. Maybe related: 1. no mozilla account for syncing configured 2. running on an i5 6600K on gentoo linux (somehow fast enough)