Magento 2 extension manager 500 error

Question

I'm trying to install extensions using the extension manager, I have my access keys set, when entering the extension manager page, it's always stuck on "Please wait". The console log shows the below:

Failed to load resource: the server responded with a status of 500 (Internal Server Error)
angular.js:533 Possibly unhandled rejection: {"data":"","status":500,"config":{"method":"GET","transformRequest":[null],"transformResponse":[null],"jsonpCallbackParam":"callback","url":"index.php/extensionGrid/extensions","headers":{"Accept":"application/json, text/plain, */*","Cache-Control":"no-cache, no-store, must-revalidate","Pragma":"no-cache","Expires":0}},"statusText":"Internal Server Error","xhrStatus":"complete"}
(anonymous) @ angular.js:533
/setup/index.php/extensionGrid/extensions:1 Failed to load resource: the server responded with a status of 500 (Internal Server Error)
angular.js:533 Possibly unhandled rejection: {"data":"","status":500,"config":{"method":"GET","transformRequest":[null],"transformResponse":[null],"jsonpCallbackParam":"callback","url":"index.php/extensionGrid/extensions","headers":{"Accept":"application/json, text/plain, */*","Cache-Control":"no-cache, no-store, must-revalidate","Pragma":"no-cache","Expires":0}},"statusText":"Internal Server Error","xhrStatus":"complete"}
(anonymous) @ angular.js:533
angular.js:12571 POST https://website.com/setup/index.php/session/prolong 500 (Internal Server Error)
(anonymous) @ angular.js:12571
n @ angular.js:11748
(anonymous) @ angular.js:11263
(anonymous) @ angular.js:6988
$digest @ angular.js:8414
$apply @ angular.js:8817
(anonymous) @ angular.js:12941
23angular.js:12571 GET https://website.com/setup/index.php/session/unlogin 401 (Unauthorized)

Answer 1

The issue was solved by manually installing the modules using composer, the Magento 2.3.5 documentation says that you need to manually use composer, it is now fixed in 2.4.x