I wrote this in November 2024 but, for some reason, I didn’t publish it. Oops. Stirling-PDF offers a suite of useful, self-hosted, PDF-related tools, with support for dark mode. Genuinely, this is an amazing bundle of tools, all in one place. You can try a demo here. The only tool that I have tried but not managed to get working is signing a PDF with a .p12 certificate, and it does say that this is a work in progress. You can get view the project on Github. I found this part of the project...
