Bootstrap 4 Hidden vs Responsive Display Utilities - YouTube
Bootstrap Display
טוויטר \ Bootstrap בטוויטר: ""Block buttons” are going to be easier and more responsive than ever in our next v5 pre-release! We've dropped the .btn-block class for new .d-grid and .gap-* utilities.
NEW: Bootstrap Blocks | Pinegrow Web Editor
The moving block bootstrap for time series - The DO Loop
Bootstrap Editor - B3 & B4 layout builder and widgets in CKEditor | Drupal.org