Filter for trade secrets or variants in general

[Bernhard Jung]

It would be helpful to be able to filter the list of trade secrets in the dropdown for special ability trade secrets. The list is extremely long which makes it hard to find what you want. Especiall if you just want to check what options are there for example all the stuff a alchemist can select there is no way to get a quick overview.

This would also be helpful in case of other variants, for example to filter spells to show only the spells a hero already knows.