@loplady thanks for that info. Coincidentally, I know of two people online who had strokes while on transdermal estrogen. While we can't say for sure HRT is the cause, it’s a sobering reminder of the statistics we have to weigh.

Generally, the transdermal patch is thought to have a much lower clotting risk than the oral version. However, I came across a 2023 review by Dr. Leslie Cho, a cardiologist at the Cleveland Clinic, where she pointed out that the actual quality of studies on this specific safety aspect is still surprisingly 'low', see table 5:
https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.122.061559
At the end of the day, your physician and cardiologist are definitely the best ones to help you weigh the bone benefits against the cardiovascular risks since they know your health history best.