Loading of dictionaries is too slow

The loading of a dictionary is a foreground task. It should be made to be a background task, with a progress bar.

Changing selection in the list of books should automatically cancel loading.

Maybe there is a better way to get the list of terms in the dictionary.

Maybe there is a better way to show the list of terms (tree, "first letter" links, ...).

Looking up a single term in a dictionary should be fast. E.g. clicking on a Strong's link, then a Morph link.