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Recommendations (for and against) are my personal opinion only and may be out of date.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? As of December 2021 I've updated most of the sites I look after to Drupal 9 (experience: mixed). I haven't decided how to label future version compatibility as D10 will be coming soon as well. The upgrade_status module is superb. You're bound to have issues with composer. Also watch out for a nasty session headers bug with redirect_after_login.

(1 modules in list)
Module name or machine name
Any text in the notes
Name D8 Personally Tested Last Updated
Twig VarDumper (twig_vardumper) 2019-12-30

d.o. page

"Essential"

Much faster than using kint, with colour coding, and still works nicely within narrow DOM elements.
Make sure you install using composer, as it has symfony dependencies.

Enabling twig debugging in the first place:

Also make sure you've activated twig debugging properly (including enabling the settings.local.php file in settings.php, and adding the debug setting to development.services.yml)
Potential gotcha - settings.local.php needs to be in /sites/default (or whichever), not just /sites/
If Twig debugging isn't enabled, the symptom is you don't see any output for the dump() commands.

Usage Tip:

- Hover over the keys and you get a tooltip that says 'Public method','Protected property' etc.