Pasting doesn't work

[FabijanC]

Steps to reproduce

1. Have lowercase content in the clipboard
2. Paste it under material
3. Observe that the characters cannot be used in anagram

Feature request

Also support pasting in the anagram input field. On paste, it would check the material letters and if everything from the clipboard is present in the material, it would remove those letters from the material and add them into the anagram. If pasting not possible, it would warn the user of this, perhaps by displaying a (short-lived?) text above or below the input field, definitely not an alert.