Method contentFailedToFetch

src/core/fetch/index.js:114–116

        // and a handler that is called if content failed to fetch
        const contentFailedToFetch = _ => {
          this._fetchFallbackPage(path, qs, cb) || this._fetch404(file, qs, cb);
        };

        // attempt to fetch content from a virtual route, and fallback to fetching the actual file
        if (!this.isRemoteUrl) {