Blank page when i click on a post

Hello,

I have a blank page when i click on a Post :
see this 9s video :
https://youtu.be/RAaC8vAqXRk
Many Thanks for your help, best regards, Arnaud

Frontend error page:
https://www.ignition.ws/regles/boite-a-idees/vos-idees/4-cr%C3%A9ation-de-d6-en-bois

System Information
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Database Connection Collation utf8_general_ci
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