luceos Sry but i don't get it.
I executed chown -R www-data /var/www/html/storage/formatter
I executed chown -R flarum /var/www/html/storage/formatter
I executed chmod 777 /var/www/html/storage/formatter
But it still shows the Error
TypeError thrown with message "Argument 1 passed to Flarum\Formatter\Event\Rendering::__construct() must be an instance of s9e\TextFormatter\Renderer, instance of __PHP_Incomplete_Class given, called in /var/www/html/vendor/flarum/core/src/Formatter/Formatter.php on line 78
Stacktrace:
#54 TypeError in /var/www/html/vendor/flarum/core/src/Formatter/Event/Rendering.php:38
#53 Flarum\Formatter\Event\Rendering:__construct in /var/www/html/vendor/flarum/core/src/Formatter/Formatter.php:78
#52 Flarum\Formatter\Formatter:render in /var/www/html/vendor/flarum/core/src/Post/CommentPost.php:173
#51 Flarum\Post\CommentPost:getContentHtmlAttribute in /var/www/html/vendor/illuminate/database/Eloquent/Concerns/HasAttributes.php:438
#50 Illuminate\Database\Eloquent\Model:mutateAttribute in /var/www/html/vendor/illuminate/database/Eloquent/Concerns/HasAttributes.php:340
#49 Illuminate\Database\Eloquent\Model:getAttributeValue in /var/www/html/vendor/illuminate/database/Eloquent/Concerns/HasAttributes.php:313
#48 Illuminate\Database\Eloquent\Model:getAttribute in /var/www/html/vendor/flarum/core/src/Database/AbstractModel.php:118
#47 Flarum\Database\AbstractModel:getAttribute in /var/www/html/vendor/illuminate/database/Eloquent/Model.php:1382
#46 Illuminate\Database\Eloquent\Model:__get in /var/www/html/vendor/flarum/core/src/Api/Serializer/BasicPostSerializer.php:47
#45 Flarum\Api\Serializer\BasicPostSerializer:getDefaultAttributes in /var/www/html/vendor/flarum/core/src/Api/Serializer/AbstractSerializer.php:71
#44 Flarum\Api\Serializer\AbstractSerializer:getAttributes in /var/www/html/vendor/tobscure/json-api/src/Resource.php:169
#43 Tobscure\JsonApi\Resource:getAttributes in /var/www/html/vendor/tobscure/json-api/src/Resource.php:75
#42 Tobscure\JsonApi\Resource:toArray in /var/www/html/vendor/tobscure/json-api/src/Document.php:187
#41 Tobscure\JsonApi\Document:Tobscure\JsonApi\{closure} in [internal]:0
#40 array_map in /var/www/html/vendor/tobscure/json-api/src/Document.php:186
#39 Tobscure\JsonApi\Document:toArray in /var/www/html/vendor/tobscure/json-api/src/Document.php:224
#38 Tobscure\JsonApi\Document:jsonSerialize in /var/www/html/vendor/flarum/core/src/Api/JsonApiResponse.php:29
#37 Flarum\Api\JsonApiResponse:__construct in /var/www/html/vendor/flarum/core/src/Api/Controller/AbstractSerializeController.php:113
#36 Flarum\Api\Controller\AbstractSerializeController:handle in /var/www/html/vendor/flarum/core/src/Api/Client.php:71
#35 Flarum\Api\Client:send in /var/www/html/vendor/flarum/core/src/Forum/Content/Index.php:91
#34 Flarum\Forum\Content\Index:getApiDocument in /var/www/html/vendor/flarum/core/src/Forum/Content/Index.php:59
#33 Flarum\Forum\Content\Index:__invoke in /var/www/html/vendor/flarum/core/src/Frontend/Frontend.php:65
#32 Flarum\Frontend\Frontend:populate in /var/www/html/vendor/flarum/core/src/Frontend/Frontend.php:57
#31 Flarum\Frontend\Frontend:document in /var/www/html/vendor/flarum/core/src/Frontend/Controller.php:34
#30 Flarum\Frontend\Controller:handle in /var/www/html/vendor/flarum/core/src/Http/RouteHandlerFactory.php:40
#29 Flarum\Http\RouteHandlerFactory:Flarum\Http\{closure} in /var/www/html/vendor/flarum/core/src/Http/Middleware/DispatchRoute.php:67
#28 Flarum\Http\Middleware\DispatchRoute:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#27 Zend\Stratigility\Next:handle in /var/www/html/vendor/flarum/core/src/Http/Middleware/ShareErrorsFromSession.php:58
#26 Flarum\Http\Middleware\ShareErrorsFromSession:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#25 Zend\Stratigility\Next:handle in /var/www/html/vendor/flarum/core/src/Http/Middleware/SetLocale.php:51
#24 Flarum\Http\Middleware\SetLocale:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#23 Zend\Stratigility\Next:handle in /var/www/html/vendor/flarum/core/src/Http/Middleware/AuthenticateWithSession.php:34
#22 Flarum\Http\Middleware\AuthenticateWithSession:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#21 Zend\Stratigility\Next:handle in /var/www/html/vendor/flarum/core/src/Http/Middleware/RememberFromCookie.php:52
#20 Flarum\Http\Middleware\RememberFromCookie:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#19 Zend\Stratigility\Next:handle in /var/www/html/vendor/flarum/core/src/Http/Middleware/StartSession.php:62
#18 Flarum\Http\Middleware\StartSession:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#17 Zend\Stratigility\Next:handle in /var/www/html/vendor/flarum/core/src/Http/Middleware/CollectGarbage.php:48
#16 Flarum\Http\Middleware\CollectGarbage:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#15 Zend\Stratigility\Next:handle in /var/www/html/vendor/flarum/core/src/Http/Middleware/ParseJsonBody.php:29
#14 Flarum\Http\Middleware\ParseJsonBody:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#13 Zend\Stratigility\Next:handle in /var/www/html/vendor/flarum/core/src/Http/Middleware/HandleErrorsWithWhoops.php:43
#12 Flarum\Http\Middleware\HandleErrorsWithWhoops:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#11 Zend\Stratigility\Next:handle in /var/www/html/vendor/zendframework/zend-stratigility/src/MiddlewarePipe.php:83
#10 Zend\Stratigility\MiddlewarePipe:process in /var/www/html/vendor/middlewares/request-handler/src/RequestHandler.php:84
#9 Middlewares\RequestHandler:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#8 Zend\Stratigility\Next:handle in /var/www/html/vendor/middlewares/base-path-router/src/BasePathRouter.php:97
#7 Middlewares\BasePathRouter:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#6 Zend\Stratigility\Next:handle in /var/www/html/vendor/middlewares/base-path/src/BasePath.php:53
#5 Middlewares\BasePath:process in /var/www/html/vendor/zendframework/zend-stratigility/src/Next.php:52
#4 Zend\Stratigility\Next:handle in /var/www/html/vendor/zendframework/zend-stratigility/src/MiddlewarePipe.php:83
#3 Zend\Stratigility\MiddlewarePipe:process in /var/www/html/vendor/zendframework/zend-stratigility/src/MiddlewarePipe.php:72
#2 Zend\Stratigility\MiddlewarePipe:handle in /var/www/html/vendor/zendframework/zend-httphandlerrunner/src/RequestHandlerRunner.php:95
#1 Zend\HttpHandlerRunner\RequestHandlerRunner:run in /var/www/html/vendor/flarum/core/src/Http/Server.php:46
#0 Flarum\Http\Server:listen in /var/www/html/public/index.php:22
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