Installation successful & ABAP Quickfix S4 visible in menu but inactive

After successful installation of 'ABAP Quick Fix 1.0.16' and 'ABAP QuickFix S4 Conversion 1.4.3' in Eclipse Version: 2025-09 (4.37.0) the ABAP Quickfix S4 is visible in menu 'Windows-> Preferences-> ABAP Development-> Quickfix S4' and can be configured. Unfortunately when using 'Ctrl + 1' on a select single it doesn't offer the S4 quickfixes (but other quick fixes are shown if applicable, so quick fixes generally work). I don't find an 'error' in the Quick Fix S4 configurations and tutorials about quick fix S4 show that these quick fixes are available for select single via 'Ctrl + 1'. Many thanks Reiner