Short term gains are going to be taxes at your marginal rate which is going to be high when you put your normal year earnings and capital gains together.
I would suggest posting your question in the support section rather then the community. With luck, superuser Tom Young will see it. Especially if it is the result of a employee stock option plan.
Disclaimer: Not a tax professional. Information gathered from internet links. Anything dated in June 2019 was posted in prior years and is before the 2019 limits and changes.
