Why in Pro can't I: ctrl-w

[Tallis]

Highlight an item in the bitmap gallery, hit the delete key, and have the thing disappear?

Have several drawings open, and successfully ctrl-tab to switch between them, but when I'm ready to close one of them, ctrl-w doesn't close it, but displays the apparently hardwired "import from web" box?

Isn't ctrl-w standard to close subwindows in most/all windows apps?

Thanks for any insight.

ps- ctrl-w in windows explorer closes it, ctrl-w in Word closes the active open document. ctrl-w in photoshop closes the active open document. i can go on.... I use it all the time.