thank you for your reply.
I didn’t find much more in the gitlab docker console
==> /var/log/gitlab/mattermost/current <==
2023-12-03_21:50:23.46261 {"timestamp":"2023-12-03 21:50:23.462 Z","level":"debug","msg":"plugin started","caller":"plugin/hclog_adapter.go:52","plugin_id":"com.mattermost.demo-plugin","wrapped_extras":"path/var/opt/gitlab/mattermost/plugins/com.mattermost.demo-plugin/server/dist/plugin-linux-amd64pid1451"}
2023-12-03_21:50:23.46288 {"timestamp":"2023-12-03 21:50:23.462 Z","level":"debug","msg":"waiting for RPC address","caller":"plugin/hclog_adapter.go:52","plugin_id":"com.mattermost.demo-plugin","wrapped_extras":"path/var/opt/gitlab/mattermost/plugins/com.mattermost.demo-plugin/server/dist/plugin-linux-amd64"}
==> /var/log/gitlab/mattermost/mattermost.log <==
2023-12-03_21:50:26.46498 {"timestamp":"2023-12-03 21:50:26.464 Z","level":"warn","msg":"plugin failed to exit gracefully","caller":"plugin/hclog_adapter.go:72","plugin_id":"com.mattermost.demo-plugin"}
2023-12-03_21:50:26.46572 {"timestamp":"2023-12-03 21:50:26.465 Z","level":"error","msg":"plugin process exited","caller":"plugin/hclog_adapter.go:79","plugin_id":"com.mattermost.demo-plugin","wrapped_extras":"path/var/opt/gitlab/mattermost/plugins/com.mattermost.demo-plugin/server/dist/plugin-linux-amd64pid1451errorsignal: killed"}
2023-12-03_21:50:26.46584 {"timestamp":"2023-12-03 21:50:26.465 Z","level":"error","msg":"Unable to activate plugin","caller":"app/plugin.go:171","plugin_id":"com.mattermost.demo-plugin","bundle_path":"/var/opt/gitlab/mattermost/plugins/com.mattermost.demo-plugin","error":"unable to start plugin: com.mattermost.demo-plugin: timeout while waiting for plugin to start"}