There is a major disconnect between F12DT and IE11's frame window. Like with firebug, when you press f5, it propagates the key-combo to frame. In F12 DT of IE11, you need to click on browser window to activate the frame, even though the F12 DT was fired on the same frame.
Also, IE11 won't allow you to drag a link to a tab as IE10 does... this is a huge productivity killer!
Finally, in other browsers' developer tools, you can use Ctrl+click on URL to open it in new tab. This shortcut is unfortunately not available in F12 dev tools.
791981: F12 developer tools: Cannot select and paste multiple CSS rules and properties.
792543: F12 developer tools: CSS rule copies with 3 space indentation instead of 4.
797447: F12 developer tools: "Copy elements with styles" ignores @font-face.
798009: F12 developer tools: quick glance at elements' dimensions (height, width, border-radius) and images preview.
798021: F12 developer tools: Color picker and Ruler tools.
798046: F12 developer tools: Visual Studio 2012+ like priority color palette.
800084: F12 developer tools: tools: Ability to toggle element states.
801923: F12 developer tools: media query overrides for debugging layout.
805145: F12 developer tools: Ability to quick edit start-tag and its corresponding end-tag.
805163: F12 developer tools: Change numeric values using keyboard up/down keys.