Ajax commands fail silently if there was an exception

This is not just Views preview - it's all AJAX commands.

This is perhaps an example of the problem: https://github.com/TolstoyDotCom/drupal_use_ajax_example

I haven't looked into whether 'use-ajax' already has a way to deal with such things and I haven't looked into how to spot such issues from the Javascript side.

I don't think it would be a good idea to let the user know the specific error message or show a stack trace, but showing something like 'An error occurred, please contact an administrator' in the dialog would be a good idea.

Not an issue any more. On crash (wrong function call or db crash) in Ajax call, the following error message is displayed

Oops, something went wrong. Check your browser's developer console for more details.

Tested on 10.2.5