https mattermost with context and http onlyoffice integration issues

[wensimin]

Hello, I have an address where mattermost runs on https and has context. The path is similar to the following.
https://mydomain/mattermost/
When I click open file in ONLYOFFICE , the request is
https://mydomain/plugins/com.onlyoffice.mattermost/api/editor?file=filekey
So a 404 error occurred
Since I couldn't find a place to modify the context, and the mattermost siteurl didn't work here, I modified the hard coding.
export const ONLYOFFICE_PLUGIN_API = `/mattermost/plugins/${pluginName}/api`;
The request worked, but since my onlyoffice is on http, a mixed-content error occurred.
http://onlyoffice-domain/web-apps/apps/api/documents/api.js
Is there anything you can help me with, thank you