Useful Drupal modules

Click on the module name for notes, comments, patches.
Recommendations (for and against) are my personal opinion only and may be out of date. Feel free to email with corrections/suggestions.

Why haven't you mentioned Drupal 9? I will be adding this, but as of August 2021, this site you are reading is the only Drupal site of mine I've been able to upgrade to D9, so although you can check D9 compatibility status of all modules (use upgrade_status, it's superb) I can't speak from personal experience about any of them.

(1 modules in list)
Module name or machine name
Any text in the notes
Name D8 Personally Tested Last Updated
Responsive and off-canvas menu (responsive_menu) 2020-11-18

d.o. page

This uses a JS library and works without a second copy of the menu in the HTML, and you don't need to make any changes to your existing navigation menu.

Look at the README file for instructions.
You need to install mm_menu and superfish in your libraries folder.

Note you're forced with the mobile version of the menu to have it expand to full depth (although the hack/workaround, if you want a top-level menu only,  is to hide the lower elements in CSS)

For hand-crated CSS / minimal javascript solutions, see