For the best you prime it yourself with oil and 2 topcoats latex.
Research the aplication required by a paint Sherwin Williams guarntees
for life, you use their oil primer and paint [ their product specs may
have changed]. Another point is you know nothing about the product
quality on Pre Primed. I don`t trust Pre Primed.

If you want the windows natural just use poly, oil if you want it to
amber, water base if you want it to stay as light as possibe. If you
want a darker color wood you must Pre Stain with a shellac base product
like Bix, then stain, not a job for an amature. Or the Best painting is
Ben Moore enamel underbody, sanded with 220, topcoated with Ben Moore
Satin Impervo thinned with Penetrol, again not for an amature. You can
order your windows painted I bet..