Try this:
D1 = load('stopWords.mat');
stopWords = D1.stopWords;
D2 = load('newWords.mat');
newWords = D2.newWords;
editedWords = cellfun(@(x,y)setdiff(x,y,'stable'),{newWords},stopWords, 'Unif',0); % (1x1) Cell Array (305x1) Cell
editedWordsList = editedWords{:}; % (305x1) Cell Array
It appears to produce the correct result (‘editedWordList’), although I did not examine it closely.
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