List all forms:

    find .. -iname *.ui
 
List all files containing ".tr":

    grep -rin "\.tr(" ../manuskript > list.txt

List all files containing ".translate":

    grep -rin "\.translate(" ../manuskript >> list.txt
    
Then clean list.txt, and copy it in LibreOffice Calc, then:
- Data, Filter, Advanced
- From: whole column
- No duplication
- → filter