I usually want to find and replace all, but it looks like it has been set to current/highlighted cell only (https://github.com/jupyter/notebook/pull/2131). jupyter also doesn\'t
I just had to do it urgently so shut down the notebook kernel did it from the terminal with sed
like this:
sed -i "" 's/oldword/newword/g' mynotebook.ipynb
That was on a mac which am using at the moment, but if you do it on ordinary linux the "" should be left out ie
sed -i 's/oldword/newword/g' mynotebook.ipynb
First time I ever needed to do such a thing in years but if it happened more often would be good if it could be done from the browser.