Plugins from Marketplace not working

System Information
  • Strapi Version: 4.1.9
  • Operating System: Windows 10
  • Database: Postgres
  • Node Version: 12.22.4
  • NPM Version: 6.14.14
  • Yarn Version: 1.22.18


I created a Strapi project using the latest version 4.1.9 (executing the command npx create-strapi-app@latest my-app). I dockerized it along with an image of Postgres. Everything works fine excepted when I introduce some plugins from marketplace.

I really need the following plugins:

I installed it executing the command yarn add @strapi/plugin-documentation, the dependency “@strapi/plugin-documentation”: “^4.1.9” has been correctly added to package.json, I regenerated node_modules that now includes the plugin. Nothing changed neither in the admin panel nor in the src folder.
What should I expect and what am I missing?

I discovered today the existence of this plugin since I was desperately wanted to flatten the response returned by the Strapi API in version 4 (with data and attributes fields). I followed this guide for the installation and configuration. Also in this case package.json and node_modules have been correctly updated.
I created the file ./config/plugins.js like this:

module.exports = ({ env }) => ({
  // ..
 'transformer': {
    enabled: true,
    config: {
      prefix: '/api/',
      responseTransforms: {
        removeAttributesKey: true,
        removeDataKey: true,
  // ..

The absence of a definition for the attribute “resolve” causes the following error:

strapi_1 | [2022-05-02 17:16:19.878] debug: ?? Server wasn’t able to start properly.

strapi_1 | [2022-05-02 17:16:19.879] error: The “path” argument must be of type string. Received undefined

strapi_1 | TypeError [ERR_INVALID_ARG_TYPE]: The “path” argument must be of type string. Received undefined

strapi_1 | at new NodeError (internal/errors.js:322:7)

strapi_1 | at validateString (internal/validators.js:124:11)

strapi_1 | at join (path.js:1148:7)

strapi_1 | at Object.loadPlugins (/opt/node_modules/@strapi/strapi/lib/core/loaders/plugins/index.js:89:34)

strapi_1 | at async Strapi.loadPlugins (/opt/node_modules/@strapi/strapi/lib/Strapi.js:284:5)

strapi_1 | at async Promise.all (index 1)

strapi_1 | at async Strapi.register (/opt/node_modules/@strapi/strapi/lib/Strapi.js:316:5)

strapi_1 | at async Strapi.load (/opt/node_modules/@strapi/strapi/lib/Strapi.js:414:5)

strapi_1 | at async Strapi.start (/opt/node_modules/@strapi/strapi/lib/Strapi.js:163:9)

strapi_1 | info Visit yarn run | Yarn for documentation about this command.

strapi_1 | error Command failed with exit code 1.

Setting the “resolve” attribute with a fake path makes the application running but obviously the plugin has no effect.
Is the plugin supported in the latest version of Strapi? Why do I obtain this error even if it’s installed as a node module and it’s not a custom one? Is there an alternative to strapi-plugin-transformer in case I want to receive a response closer to the one returned by Strapi v3 without the fields “data” and “attributes”?

I truly hope someone could help me to solve my issue, I can provide you with further details in case you need them.

I’m having the exact same issue. Even added the "strapi": {"kind": "plugin",} to the pkg.json file. No joy. After digging on this for a while I’ve found several other devs asking the same question but getting no responses.

strapi exited with code 1 strapi | yarn run v1.22.19 strapi | $ strapi develop strapi | 
[2022-08-26 17:53:10.790] debug: ⛔️ Server wasn't able to start properly. strapi | [2022-08-26 17:53:10.796] error: The "path" argument must be of type string. Received undefined strapi | 
TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined strapi | at new NodeError (node:internal/errors:387:5) strapi | at validateString 
(node:internal/validators:121:11) strapi | at join (node:path:1172:7) strapi | at Object.loadPlugins (/opt/node_modules/@strapi/strapi/lib/core/loaders/plugins/index.js:88:34) strapi | at async 
Strapi.loadPlugins (/opt/node_modules/@strapi/strapi/lib/Strapi.js:319:5) strapi | at async 
Promise.all (index 2) strapi | at async Strapi.register (/opt/node_modules/@strapi/strapi/lib/Strapi.js:355:5) strapi | at async Strapi.load 
(/opt/node_modules/@strapi/strapi/lib/Strapi.js:456:5) strapi | at async Strapi.start 
(/opt/node_modules/@strapi/strapi/lib/Strapi.js:198:9) strapi | error Command failed with exit code 1. 
strapi | info Visit for documentation about this command.

"dependencies": {
"@strapi/plugin-i18n": "4.3.6",
"@strapi/plugin-users-permissions": "4.3.6",
"@strapi/strapi": "4.3.6",
"better-sqlite3": "7.4.6",
"pg": "^8.8.0",
"strapi-plugin-duplicate-button": "^1.0.4"
 "strapi": {
    "kind": "plugin",

Anyone? Beuller...