I had the same issue: Filing 2019 taxes online, I kept getting error messages about Form 8960 Worksheet, which prevented me from being able to e-file.
Here is the solution:
1. Save your online return documents as a .tax2019 file (tax tools, tools, save my online return)
2. Download the desktop version of TurboTax 2019 (for Mac or PC).
3. After initial download, the application may need to process a couple of updates. Once that's finished go into the desktop app and choose "File", "Open Return". Then, browse your computer for the .tax2019 file you saved in step 1.
This solved the issue for me. Good Luck!
