PHP Startup: Unable to load dynamic library ‘’ on heroku push

  git, heroku, mbstring, php, symfony

I’m trying to push my git php project (symfony) using heroku but this error appends each time.
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In the documentation, it’s written that this extension sould be automatically downloaded by adding "ext-mbstring" in composer.json but it not working for me.

Has anyone ever encountered this problem before?

I tried 1000 times pushs and I’m totally desperate :'(

Thank you 🙂

Source: Symfony Questions