In Game of Thrones S8E4, Daenerys went to Dragonstone with her court and the Unsullied when...
Her fleet is attacked by Euron, Rhaegal killed, Missandei captured and (at least a part of) her fleet destroyed.
We see Tyrion and Varys have a discussion on Dragonstone. Some unspecified time later they turn up with Daenerys and some Unsullied at the gates of King's Landing. I am aware that Dragonstone is both, close to King's Landing and not for away from the continent. But...
Even if Daenerys has some ships left, it is clear that Euron's fleet is in control of the waters around Dragonstone and Drogon is of limited use in defending against them. It seems unlikely that Euron will allow even a part of Daenerys' army to leave the island. It seems also unlikely that Tyrion, Varys, Grey Worm and about 100 Unsullied have been riding on Drogon one-by-one to the continent (without leaving an option to quickly retreat to Dragonstone).
Considering that the travel to King's Landing is shown off screen, there seems to be an obvious way how she could have made it there. What am I missing?