§ 18. Duration of lien under contract for a public improvement. If the lien is for labor done or materials furnished for a public improvement, it shall not continue for a longer period than one year from the time of filing the notice of such lien, unless an action is commenced to foreclose such lien within that time, and a notice of the pendency of such action is filed with the comptroller of the state or the financial officer of the public corporation with whom the notice of such lien was filed; or unless an extension to such lien is filed with the comptroller of the state or the financial officer of the public corporation with whom the notice of such lien was filed within one year from the filing of the original notice of lien, continuing such lien and such lien shall be redocketed as of the date of filing such extension. Such extension shall contain the names of the lienor and the contractor or subcontractor for whom the labor was performed or materials furnished, a description of the public improvement upon which the labor was performed and materials expended, the amount of such lien, and the date of the filing of the notice of lien. No lien shall be continued by such extension for more than one year from the filing thereof. In the event an action is not commenced to foreclose the lien within such extended period, such lien shall be extinguished unless an order be granted by a court of record or a judge or justice thereof, continuing such lien, and a new docket be made stating such fact. No lien shall be continued by such order for more than one year from the granting thereof, but a new order and entry may be made in each of two successive years. If a lienor be made a party defendant in an action to enforce another lien, and the plaintiff or such defendant has filed a notice of the pendency of the action within the time prescribed in this section, the lien of such defendant is thereby continued. The provision of this section in regard to continuing liens shall apply to liens discharged by deposit or by order on the filing of an undertaking. This section is hereby declared to be a remedial statute and is to be construed liberally to secure the beneficial interests and purposes thereof.