In Chrome, a pinned tab will close when you hit Cmd-W, which is never what I want to happen. E.g., I have Gmail pinned, I open several more tabs, then at some point type Cmd-W several times to close those tabs, but if I type one extra Cmd-W my Gmail tab goes away (and the window closes). Again, I never want pinned tabs to be closed that way. The whole idea of pinning something is to make sure it stays in place. That's what pinning means.

It's really irritating (as you can probably tell).