I use Sylpheed on a Windows PC. I don't find it ugly, although I can see that some people might find the app 'old fashioned' in appearance. I switched to Sylph

I use Sylpheed on a Windows PC. I don't find it ugly, although I can see that some people might find the app 'old fashioned' in appearance. I switched to Sylpheed from Thunderbird, which is arguably uglier, slower and more clunky in operation (at least on Windows). In an age of fat, slow, memory-hogging Electron apps (often produced by large companies with lots of developers), Slypheed is a refreshing example of a slim, cross-platform desktop app maintained by just a single developer. It should serve as inspiration for others.