Whenever any city, borough, incorporated town, township or school district has heretofore filed, in the office of the prothonotary of the proper county, any tax or municipal claim, and the city, borough, incorporated town or township, or school district has not, within the period of five years after the date on which any such claim was filed, sued out a writ of scire facias to reduce the same to judgment; or in the case of a tax or municipal claim has not, within said period of five years filed a suggestion of nonpayment and an averment of default, or whenever any writ of scire facias has been issued to reduce any such claim to judgment, and by reason of defense or any other court proceedings, judgment has not been entered within the period of five years after the date on which such writ was issued; or whenever any such tax or municipal claim has been reduced to judgment and the city, borough, incorporated town, township or school district has not, within the period of five years after the date on which such judgment was entered; or within five years after the date on which such judgment was last revived, filed a suggestion of nonpayment and an averment of default, or sued out a writ of scire facias to revive the same, then in any such case, any such city, borough, incorporated town, township or school district may, within six months after the passage and approval of this act, issue its praecipe for a writ of scire facias on any such tax or municipal claim and proceed to judgment in the manner provided by law to obtain judgments upon tax, or municipal claims; or in case a writ of scire facias has been issued, but the same has not been reduced to judgment within five years from the date of issuance, issue its praecipe for an alias writ of scire facias on any such tax or municipal claim and proceed to judgment in the manner provided by law to obtain judgments upon tax, or municipal claims; or in the case of a tax or municipal claim, where no judgment has been entered, file a suggestion of nonpayment and an averment of default; or in case judgment has been entered on a tax or municipal claim, either file a suggestion of nonpayment and an averment of default or issue its praecipe for a writ of scire facias on any such judgment and proceed to judgment in the manner provided by law to obtain judgments of revival, and such claim or judgment so entered or revived shall be a valid claim or judgment and be a lien upon the real estate upon which it was a lien at the time the claim was filed or the judgment was entered, and said claim or judgment may be revived, or further revived and collected as other claims or judgments upon tax or municipal claims are revived and collected: Provided, however, That the lien of any such claim or judgment shall not reattach against any real estate transferred to any purchaser during the time when the lien of any such tax, or municipal claim or judgment was lost, nor shall the lien of any such claim or judgment impair or affect the priority of the lien of any mortgage or other lien which gained priority because of the failure of the city, borough, incorporated town, township or school district to sue out the writ of scire facias, or file a suggestion of nonpayment and an averment of default within the five year period, or was entered of record during the time the lien of such tax or municipal claim or judgment was lost.