function plugin(markdownIt, _options) { const defaultRender = markdownIt.renderer.rules.fence || function(tokens, idx, options, env, self) { return self.renderToken(tokens, idx, options, env, self); }; markdownIt.renderer.rules.fence = function(tokens, idx, options, env, self) { const token = tokens[idx]; if (token.info !== 'justtesting') return defaultRender(tokens, idx, options, env, self); return `
JUST TESTING: ${token.content}