I've used ClipX since its inception in 2004, and was shocked to learn it was recently updated by the original author for a major 2.0 revision... 18 years later! The FAQ also states that he never sold it, so it remains 100% crapware free.
I used to joke that it took Microsoft until Win 11 to create their own clipboard manager, and even then it didn't hold a candle to the 18 year old ClipX 1.0
Why is the installer unsigned? I Win11 warnings about installing
No idea, email him and ask? I don't develop desktop apps but I'm assuming it's because the original installer didn't.
Why not just use WIN KEY WITH V KEY?
ClipX has plugins that give you way more features. As a web developer I used the color picker plugin to copy the hex code of the pixel beneath my mouse to the clipboard when a hotkey is pressed, although it could be configured in many other ways.