Get your taxes done using TurboTax

No.  Just quicker to pay the IRS directly and then you know they got it and applied it to the right year.

You can pay here and be sure to pick the right year.  And pay on time.  I always pay the 4th quarter before Dec 31 and don't wait until Jan 15.  
https://www.irs.gov/payments

See this screen on how to apply estimates.  Now you should pick 2019.