jackwayneright

The sound is coming from macOS, not Alfred. If you press your Hotkey when nothing is selected, you’ll both hear the beep and see the Edit menu of the app you’re in flash. If you press ⌘C in the same situation, you’ll get exactly the same thing. Copying is part of how the feature works.

You may still be able to get around it and find some API to get the text selection of apps, but I suspect it will end up being a finickier solution that might not work on non-native apps. Can’t say for sure, as I haven’t researched it.

Alternatively, copy the text to the clipboard and read it from there in the Run Script. 
 
Or, and this should be more convenient for this specific use-case, always normalise whatever text is passed-in. That would have the side-effect of fixing cases where the input is decomposed.

Alfred normalises Unicode to NFD form before passing it to scripts. If you need the raw input as entered by the user, tell Alfred to write it to a text file and read it from there.