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Recommendations (for and against) are my personal opinion only and may be out of date.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.

(130 modules in list)
Module name, text of notes
Name Notes last updated Avoid (imo) "Essential" D8 Personally Tested Sort descending
Mollom - DEPRECATED 2018-11-22
Coder 2018-11-21
Block Visibility Groups 2017-02-08
Flood Control 2017-02-08
Feeds 2018-11-21
Alexa 2017-02-06
Field collection 2017-02-08
Refreshless 2018-11-21
Trash 2018-11-22
CKEditor Custom Config 2018-12-06
Node Export 2018-11-20
Twig Extensions 2020-02-13
Restrict Login or Role Access by IP Address 2017-02-08
Entity Access Audit 2018-11-22
Group 2017-02-07
Features 2018-09-17
Simple OAuth 2018-11-22
AddToAny Share Buttons 2017-02-07
Autofocus 2017-02-08
Image Lazyloader 2017-02-27
Autosave 2017-02-08
Automatic Nodetitles 2017-02-07
Datetime Range 2018-11-19
Twig Tweak 2020-11-08
Unique field ajax 2017-02-08
View Migration 2018-11-23
Comment Notify 2018-12-15
Devel 2020-03-05
Add another 2019-12-21
Responsive and off-canvas menu 2020-11-18
SEO Checklist 2018-11-19
Configuration Update Manager 2018-11-19
Better Exposed Filters 2018-11-20
Real Name 2018-11-21
Computed Field 2018-11-25
Toolbar menu 2019-12-21
Views Contextual Filters OR 2020-12-07
Coffee 2020-05-10
Configuration Override Warn 2018-11-19
D8 Editor Advanced link 2018-11-20
Snippet Manager 2018-11-21
Environment Indicator 2018-11-26
Content access 2019-12-21
Rules 2021-04-12
HMS Field 2017-02-08
Two Factor Authentication 2018-09-17
AJAX Comments 2018-11-23
Automatic User Names 2019-02-20
Layout builder 2018-11-26
Login email or username 2019-12-21
Views Aggregator Plus 2021-05-12
Configuration Read-only 2018-12-07
Password policy 2018-11-26
Automatic Entity Label 2018-11-20
Field Formatter Condition 2018-11-21
Webform Views Integration 2018-11-26
Menu position 2020-01-26
Conditional Fields 2021-08-10
Telephone 2017-02-08
Field Permissions 2018-11-21
Bamboo Twig 2018-11-19
ClamAV 2018-11-20
Menu Token 2018-11-21
CKEditor Wordcount 2018-12-06
Save edit 2019-12-21
AudioField 2021-09-02
TagCloud 2017-02-20
Advanced Page Expiration 2018-09-17
Views Secondary Row 2018-11-19
Pathologic 2018-11-22
Views exposed form layout 2018-11-21
Honeypot 2020-03-02
Ngrok for drupal 2019-12-21
Exclude Node Title 2017-02-06
Twig Xdebug 2017-02-08
Redirect 2017-02-20
Webform 2020-02-09
SMTP Authentication Support 2018-11-20
Entity Embed 2018-11-21
Twig VarDumper 2019-12-30
Flippy 2017-02-06
Prepopulate 2017-02-08
Token 2017-02-24
General Data Protection Regulation 2018-11-19
Nagios 2018-11-21
Mydropwizard 2019-03-13
Warden 2018-09-17
Field Tools 2018-11-22
CSS Editor 2019-12-21
Required by role 2018-11-20
Captcha 2019-04-01
Rabbit hole 2020-02-17
Web Profiler 2017-02-26
@font-your-face 2018-11-19
Config Ignore 2018-11-20
Google Authenticator login 2018-11-22
reCAPTCHA 2020-02-10
Node Page Disable 2020-11-05
PDF Reader 2017-02-07
IMCE 2017-02-08
Module builder 2017-02-26
CKEditorHeight 2018-11-19
Role Delegation 2018-11-20
User restrictions 2019-04-01
Resave nodes 2020-04-21
Memcache API and Integration 2018-11-19
Role Watchdog 2018-11-20
Serial Field 2018-11-23
Spambot 2019-04-05
Table trash 2020-04-26
Pathauto 2017-02-07
Contact Storage 2018-11-22
Flag 2017-03-13
String Overrides 2018-11-19
Allowed Formats 2018-11-20
Double Field 2018-11-23
Administration Views 2019-12-21
Upgrade Status (for Drupal 9) 2020-05-16
Entityqueue 2017-02-07
Paragraphs 2018-11-22
Structure Sync 2018-11-19
Permissions Filter 2018-11-20
Address 2018-11-24
Views taxonomy term name into ID 2019-12-21
Username policy 2020-06-24
Masquerade 2018-11-20
Metatag 2021-04-28
Field group 2019-12-21
Raven 2018-11-25
Views infinite scroll 2019-12-21