Blurry font on Macbook Pro 2017 Catalina with Dell P2419HC
Solution 1:
Your MacBook Pro's native display has 219 pixels per inch.
Your Dell display has 92 pixels per inch.
Apple's font smoothing technology is designed for high-resolution displays. MacOS used to include code to improve text on low-res screens, but it was removed a while ago.
In short: yep, text will look crappy on displays without a high pixel density using macOS.
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