MirHamid in Meta.php line 35 should be a variable but $document->direction = 'ltr'; it should be change to rtl with lang code like "fa" or "ar"
clarkwinkelmann MirHamid are you reporting a bug or are you creating a new extension? In your extension you can use the Extend\Frontend::content() PHP extender to register a callback or invokable class that will be able to change this value.
askvortsov MirHamid That's something that would need to be implemented by the language pack, or via something like https://discuss.flarum.org/d/29660-rtl-support
MirHamid askvortsov this extension do that with css that not correct i say it should be automatic all forum scripts doing that by default