Handle maxOne

[aalemayhu]

const backSide = (() => {
                let _b = b;
                if (this.settings.maxOne) {
                  _b = this.removeNestedToggles(b);
                }
                if (this.settings.perserveNewLinesInSummary) {
                  _b = replaceAll(_b, "\n", "<br />");
                }
                return _b;
              })();