"On form 8889 Line 3 Smart worksheet the Self-only coverage is $3,500. "
Yes, remember that this is just a worksheet and does not appear on the return.
"Or is there a entry to enter age 55 additional contribution?"
The IRS instructions for the 8889 say to put $3,500 for Self-only, then later say that you can add $1,000 if you are 55 or older. This is why Line 3 itself is $4,500, which is correct.
"The screens on Turbo Tax Premier 2019 desktop version are different. "
You are correct. Unfortunately, with our new system for fielding and answering questions this year, we no longer can see which version of the product you are using, and sometimes we guess wrong.
Your description of the 8889 is exactly what I would expect it to be.
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