https://mariadb.com/kb/en/library/server-system-variables/#max_allowed_packet references https://mariadb.com/kb/en/library/server-system-variables/#slave_max_allowed_packet , which seems to lead to itself (to https://mariadb.com/kb/en/library/server-system-variables/#max_allowed_packet).
Error rendering 'com.xiplink.jira.git.jira_git_plugin:git-issue-webpanel'. Please contact your Jira administrators.