Answers.Body: <p>Craft 3 knows about available plugins via the <code>vendor/craftcms/plugins.php</code> file, which stores info about all Composer packages that were installed with <code>type: craft-plugin</code> in composer.json.</p>
  
  <p>If that file doesn’t exist or is just returning an empty array, then make sure that the <code>craftcms/plugin-installer</code> Composer package is installed, and try re-requiring each of your Craft plugins. As they are (re-)installed, they should get added to <code>plugins.php</code>.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2017-08-09T08:35:48.887Z
Answers.Text: I'll check that if it happens again. Thanks!
Answers.UserDisplayName: Matthias Redl-Mann
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-08-07T20:14:29.200Z
Answers.Text: This worked for me. Thanks! I ran `composer remove <plugin>` and then ran `composer require <plugin>:<version>`. The plugins.php file now exists. For some reason it wasn't there before.
Answers.UserDisplayName: Andrew
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2017-08-08T23:07:46.517Z
Answers.LastActivityDate: 2017-08-08T23:07:46.517Z
Answers.UserDisplayName: Brandon Kelly
Body: <p>Due to problems I had with Craft 3 Beta 23 I switched back to version Beta 22 (I did this a couple of times)</p>
  
  <p>I do this by importing an sql dump of beta 22 and by directly requesting Beta 22 via composer.</p>
  
  <p>The strange thing: Craft forgets about Plugins it had installed. They simply do not appear anymore in the plugins list, although they are installed via composer and nothing changed in them.</p>
  
  <p>I cleared storage/runtime and I also cleared the DB cache via utilities, that does not help.</p>
  
  <p>Any hints why Craft does not show the plugins anymore in the list? Is there another cache?</p>
  
Tags: <plugin-development><craft3><composer>
Title: Craft 3 forgets plugins
ThreadText: # Craft 3 forgets plugins
  
  (Asked by: username_0 on 2017-08-08)
  
  Due to problems I had with Craft 3 Beta 23 I switched back to version Beta 22 (I did this a couple of times)
  
  I do this by importing an sql dump of beta 22 and by directly requesting Beta 22 via composer.
  
  The strange thing: Craft forgets about Plugins it had installed. They simply do not appear anymore in the plugins list, although they are installed via composer and nothing changed in them.
  
  I cleared storage/runtime and I also cleared the DB cache via utilities, that does not help.
  
  Any hints why Craft does not show the plugins anymore in the list? Is there another cache?
  
  **Tags:** plugin-development, craft3, composer
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2017-08-08. Score: 5 | Accepted answer
  
  Craft 3 knows about available plugins via the `vendor/craftcms/plugins.php` file, which stores info about all Composer packages that were installed with `type: craft-plugin` in composer.json.
  
  If that file doesn’t exist or is just returning an empty array, then make sure that the `craftcms/plugin-installer` Composer package is installed, and try re-requiring each of your Craft plugins. As they are (re-)installed, they should get added to `plugins.php`.
  
  > **Comments:**
  > **username_0**: I'll check that if it happens again. Thanks!  
  > **username_2**: This worked for me. Thanks! I ran `composer remove <plugin>` and then ran `composer require <plugin>:<version>`. The plugins.php file now exists. For some reason it wasn't there before.  
  
  ---
  
  