LyX 2.2 slowness

[racoon]

LyX 2.2 is very slow compared to LyX 2.1.4 (on Windows). (I have only a 
meager dual core processor though.)

For example, if I open a long document like the Users Guide and make a 
text selection bigger or smaller 2.2 stutters a lot (up to not reacting) 
while 2.1.4 works fine. I am not sure this is just the CPU load because 
there is "only" a 10 percent difference (50 vs. 40 %).

Daniel