Got a 100% reproduceable problem which I cant find any info on as to why its occurring (presuming its not supposed too :))
* select anything via CTRL C (eg image, line of text ... anything) or any method of adding to the Clipboard (EDIT / COPY or Right CLICK / COPY etc)
* If I ALT TAB to the App I want to paste into, and I have to ALT TAB more than once (eg its the 2nd or more in the serial sequence off apps presented), then going PASTE / CTRL V etc ... doesn't paste anything.
* If I go back and COPY again and this time do a single ALT TAB (eg Im coming back from the previous app which happens to be where I tried the first time) ... it works first pop. BUT ... only if its a single ALT TAB. If I now ALT TAB around a few more apps, then come straight back to where I just pasted something (without selecting anything else) ... nothing pastes again.
Its almost as if ALT TAB more than once is clearing the Clipboard.
This is on a Win 8.1, Laptop with Ext monitor attached as well as Microsoft 3000 wireless keyboard.
Actually - more testing. Its got to be MS Keyboard ... as ity doesnt happen with Laptop Keyboard. :(