This test reproduces bug SEL-272

TestClickBlankTarget
open ../tests/html/Frames.html  
selectFrame bottomFrame  
click changeBlank  
waitForPopUp _blank 10000
selectWindow _blank  
click changeSpan  
close    

And again, from the wrong frame

selectWindow null  
click changeBlank  
waitForPopUp _blank 10000
selectWindow _blank  
click changeSpan  
close    

Also try submitting a form with a _blank target

selectWindow null  
selectFrame bottomFrame  
submit formBlank  
waitForPopUp _blank 10000
selectWindow _blank  
click changeSpan  
close