I'm trying to push my git php project (symfony) using heroku but this error appends each time. enter image description here
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 :)
You are missing the libonig library on that system, which mbstring requires now.
I'm not experienced with Heroku, but it looks like they haven't updated their base images to include this library.
This other post suggests a fix that should fix your issue.
Dokku: PHP extension mbstring is missing when deploying Laravel application
