Hi ... Doing a block selection with the mouse doesn't work in combination with using shift to pass mouse functions on to the application withing Konsole. This problem only exists when the command in konsole accepts mouse interactions.

I.e. load cat /etc/passwd  .. and use <ctrl-alt-mouse selction> .. and everything works. It will also work with <ctrl-alt-shift-mouse selction>. 
But !! if you 'vim /etc/passwd' and then ':set mouse=a' ... then block select is impossible ... <shift-mouse selction> works fine .. but <ctrl-alt-shift-mouse selction> doesn't work, and neither does <ctrl-alt-mouse selction>.  .. I've confirmed this behaviour with vim, tmux and screen. 

Thanks for your time
Ax

Reproducible: Always

Steps to Reproduce:
1.vim /etc/passwd
2.:set mouse=a
3.Try to do a block-select with <ctrl-alt-shift-mouse selection> or  <ctrl-alt-mouse selection>

Actual Results:  
Nothing selects

Expected Results:  
Expect to make a block selection 

Rating this as a Minor .. It might be Normal, but I can 'unsplit' my tmux panes and use a normal <shift-mouse selection> ... and grumble a bit, its a bit cumbersome. Posting because its probably an oversight that is easy to implemet a fix for
Thx