The meme clearly states that there is no difference between nazi germany an Israel. I know the idea is to show how bad Israel is but whats actually happens is that crimes of Nazi Germany are relavated.
So congards, your helping fashists saying that Nazis werend that bad...
If you plan on doing it on a regular basis, you might want to try latex. This is going to be hard on the first one or two poster but on the long run it can save a lot of time...
Out of curiosity, what Firefox addons do you have in mind?