In 1922, the German director F. W. Murnau wanted to make a Dracula adaptation. But he didn't (couldn't?) get the rights to the novel. So he changed the title "Dracula" to "Nosferatu", renamed "Count Dracula" to "Count Orlok" and... that was about it. The movie was so obviously a beat-for-beat remake of the plot to Dracula that Bram Stoker's widow successfully sued the studio and won. The court ruled to have every copy of the movie destroyed. Fortunately, a couple copies survived and it is now known as one of the best examples of a horror movie from the silent film era.
Since this movie is so old, it's also in the public domain. This means you can watch it anywhere. Since no one has to pay any licensing fees, it's on a bunch of streaming services (and youtube). Be warned though, I recommend watching the original in black and white. Don't bother watching any colorized versions of this movie, it's better to keep the movie in a creepy black and white.
I think Nosferatu is the origin of the idea of Vampires being destroyed by sunlight, obviously one of the most influential ideas in the genre.
You're right. It's crazy how that little idea is now fully ingrained in vampire lore. I think in Bram Stoker's novel, Dracula didn't like sunlight but I don't think they ever said it would kill him.
I wonder if that idea still would've persisted if all the copies of Nosferatu had truly been destroyed... It's possible vampires would be very different today if we didn't have this movie. Crazy.
I think in Dracula he is weakened and can't use most of his supernatural powers in sunlight.