Mattermost : can’t upload plugins

Hi there,
Making my first steps with Yunohost, I stumble upon the following issue with Mattermost and custom plugins.

My YunoHost server

Hardware: VPS bought online
YunoHost version: (stable).
I have access to my server : Through SSH | through the webadmin
Are you in a special context or did you perform some particular tweaking on your YunoHost instance ? : no
If yes, please explain:
If your request is related to an app, specify its name and version: mattermost 9.5.2~ynh1

Description of my issue

I need the boards plugin, which is no longer available through the standard install. After allowing plugins uploads and ramping up MaximumFileSize both in mattermost config.json and system console, I get a « Received invalid response from the server. » error message in Mattermost. The nginx logs read

intended to send too large body: 151800112 bytes

Mattermost support advices to « Increase the value of client_max_body_size to a higher limit » in the Nginx configuration file for the Mattermost server.
But… I can’t locate the file.
Could you let me know how to ramp up the client_max_body_size?

Thx for any help anyone can provide me with ;- )
Take care!

The file is located at


Many Thx @jarod5001.
Worked like a charm.