Soverywrite, I’m not sure what text expanders are either but I think by substitutions MM is referring to the “Enable additional substitutions” check box at the bottom left of your screen shot (I had to scroll the picture down to see it). If those words you are seeing pop up somehow found their way into your “substitutions” list, that is how the feature would function (including quirky fixes, if there are conflicts). I can’t imagine how, if not done intentionally, but maybe those words got entered into the substitutions list without you being aware. It’s worth checking. To do that you will just click on the large horizontal button at the bottom of that same window in your picture. The button is titled, “Edit Substitutions…” and once in the resulting window you can view, add and remove words to be substituted (including leaving words on the list but deactivating them with yet more check boxes). I believe the idea behind substitutions is to automate and streamline time consuming character combinations and also to catch customized, commonly misspelled words not preset to be caught by the spell check dictionary. I hope this helps.
One other thing, while that advice may or may not help you to determine what’s going on, it may not help to eliminate associated problems entirely. I have been seeking help on a similar problem in another post (here: [url]Auto-correction substitution - curious behavior]) that I am frustratingly getting no responses to. Your issue seems to have a component similar to the problem I’ve experienced.
The difference is that I have deliberately entered words to be substituted but the feature is taking things too far. Scrivener is searching for words on the substitutions list even if they are contained within other words! For example, in the substitutions list, to make up for a common typing error, I entered “id” to be substituted with “I’d,” only now when I type “hide” Scrivener changes it to “HI’de” (and so on with any word containing that combination). Other words are reacting the same way like “cant” requested to change to “can’t” altering “significant” to “significan’t.” Maddening and my end sollution (you’d have to read the post) was to deselect those words from the list and forego the feature for those words. (No, I wouldn’t care for some cheese with my whine because this is the bug hunt forum after all :mrgreen: .)
Anyway, I hope the advice leads you to an answer and I don’t mean to snuff out your problem by bringing mine up, especially if they are unrelated. I just noticed a bit of similarity so thought I would mention it.