I am using TeXstudio on OSX Sierra with en_GB as my default language. When I right click on a word marked as wrong and 'Add it to the dictionary', it gets saved in the en_GB.ign file under /Applications/texstudio.app/Contents/Resources and I can see this. But, this file gets emptied every time I restart the TeXstudio app. Is there anyway to permanently save it or are my settings wrong?
So, I figured out how to solve this problem. I moved the all the en_GB files to a folder under my home directly, that I was completely sure was writable. Now, the ign file retains its state even after closing TeXstudio.